The role of the Sanctuary during the Second Colonization
The earliest structures associated with the worship of the god Apollo date back to the late 7th c. B.C. However votive offerings which came to light in Delphi allow the conclusion that the sanctuary attracted pilgrims even from faraway lands, already since the end of the 10th century B.C. The growth of the sanctuary is closely connected to two areas which shaped the social and economic evolution of Greek society: with the colonization (especially the so-called Second Colonization of the 8th-6th centuries B.C.), and with the social and political reforms within the Greek cities, particularly with tyranny. 
The sanctuary of Delphi played an important role in the establishment of the Greek colonies. It is considered that before each mission for the foundation of a colony the interested city sent an embassy to the sanctuary of Delphi. It is possible, however, that the metropolis itself, i.e. the city from which the colonists originated, had already decided upon the foundation of a colony and then requested approval of the process. In any case, before attempting to establish a colony they would consult Apollo. The oracle was provided personally to the colonist and was accompanied by a mandate based on which the latter would take on various offices such as that of the king, the religious leader, the military leader and the legislator. The sanctuary continued to monitor the development of the colonies even after their establishment. Indeed, in cases of social crisis, it recommended someone as judge in order to intervene and restore order. Such was, for example, the case of Demonax from Mantineia who was appointed as katartistir (mediator judge) at Cyrene.

The role of the Sanctuary in the sociopolitical developments within Greece
During the entire Archaic period the Delphic sanctuary was active and continuously involved in the sociopolitical changes, especially those related to societal organization. Sparta maintained very close ties with the Oracle. Despite the current existing doubts concerning Lycurgus and the reforms attributed to him, it is certain that, even from the years of Tyrtaeus, the role of Delphi in these profound changes had been significant (Her. 1, 65; Plutarch, Lycurgus 29).
There seems to be a close connection between Delphi and tyranny seeing that in many cases the priests supported the tyrants. The prophecy of the Oracle regarding Cypselus as the future tyrant of Corinth is a characteristic story delivered to us by Herodotus (5, 92). Cylon had similar support in his attempt to become tyrant of Athens; however he failed because he did not interpret the oracle correctly (Thucydides 1, 126, 5). There were, however, also cases where the sanctuary opposed tyranny, as it occurred with the Orthagorids at Sicyon (Her. 5, 67).
But when tyranny had served its purpose and could no longer meet the increasing demands of the middle and lower social layers, the sanctuary of Delphi did not hesitate to take a clear opposing stance against it. 
In Cyrene at around 550 B.C., during the reign of Battos III, the Cyreneans, who had experienced major disasters during the rule of the previous king, ‘sent (an envoy)  to Delphi to ask what regime they should  adopt in order to live in a better way. Pythia commanded that they should invite a legislator from Mantineia in Arcadia’ (Arist. Politika 7, 1319b 18-22). Similar was the position of the Oracle in regard to the late Peisistratid Tyranny: it supported the Alkmeonids -their primary opponents-, motivated the Spartans to overthrow the Athenian tyranny and assisted Cleisthenes in achieving a smooth transition from tyranny to democracy.
The people of Delphi were also involved in military conflicts, for example, during the Persian Wars where they seemed to maintain, at least initially, an attitude friendly to the Persians.

The heyday and glamour of the Panhellenic sanctuary
From the 8th century till the early 5th century BC, the sanctuary of Delphi reached its peak in authority and influence.  The more frequently people went to it for advice or information, the more enriched its expertise became on issues of geography, political balance and social frictions. Successful colonization expanded its influence and reputation and strengthened its leadership position as a Panhellenic sanctuary. Furthermore, both the colonies and the tyrants of various cities enriched the sanctuary with offerings and sacred envoys. Despite the conservativeness on matters of religion and worship, the sanctuary almost always supported the changes imposed by social needs. 
The validity of Apollo’s oracles was connected to the legislation of the cities, providing authenticity, and the role of Delphi was to guarantee social peace. The sanctuary did not offer prestige to the leaders by divine command, but instead it supported their decisions, adding a legalizing character. 

The earliest temple constructions
The Archaic period is considered to be the period when the sacred site of Delphi began to take the form known today. The first poros stone temple was built in the sanctuary of Athena Pronaia, but it was abandoned later on due to damages it had suffered during earthquakes. Similarly, the first historically documented Apollo's temple, also made of poros stone, was built within Apollo’s sanctuary.

The first votive offerings-8th and 7th c. BC
At the end of the late 8th c. B.C., along with the offerings from all over Greece, the first imports from the East arrived in Delphi. These imported offerings were brought by Greek seafarers from the interior of Asia by way of the Greek trading posts of northern Syria (Al Mina, Tyre) and the intermediary islands of Crete, Cyprus and Rhodes. During the next century, the temple of Apollo is overwhelmed by a large number of luxurious metallic wares which were produced with innovative techniques and featured unusual decorative patterns. These artifacts originated either from the ancient Near East which was home to the early Assyrian civilization, the Hittites and the state of Urartu (Armenia) or were eastern prototype imitations. Amongst the early offerings, the bronze tripods hold a dominant position. In Delphi the tripod bears a particular symbolic value because it is associated with the oracular capacity of Apollo. Moreover, it is linked to the process of providing oracles given that Pythia could capture and transmit the divine knowledge only when sitting on the tripod that linked her to the chthonic powers. 

The temples of the 6th c. B.C.
The first temple of Apollo was destroyed around the mid- 6th c. B.C., most probably by an earthquake. Shortly thereafter, the prominent family of the Alcmaeonids fled from Athens to Delphi after an unsuccessful attempt to prevent Peisistratus from establishing tyranny in their hometown. Apparently, the Alcmaeonids were pursuing their involvement in politics again as well as making alliances. Therefore, they took the initiative to raise money from the Greek cities in order to rebuild a new temple which was complete in 510 BC. In the sacred space of Athena Pronaia, respectively, a new poros stone temple was built in order to replace the old one that had been demolished by landslides.

The offerings of the 6th c. BC
Delphi was flourishing in the 6th c. BC. In 590 B.C. and as a result of the First Sacred War, the region of Krissa was dedicated to Apollo, resulting in an increase of  the Sanctuary's wealth. Given the fact that this is the period where the political power of the Sanctuary grows, the rulers take this opportunity to highlight their wealth and power by dedicating expensive offerings and statues or even entire buildings. Thus, the large numbers of pilgrims had the opportunity to admire the artistic value of the offerings.
The first treasuries were constructed during the 6th century along the Sacred Way leading to the temple of Apollo. Treasuries were small buildings-dedications to the god which sheltered precious ex votos from the donor city. The first treasury which delimited one side of the Halos, the small open-air square where outdoor rituals took place, was that of the Corinthians. It was dedicated by the tyrant of the city, Cypselus, inaugurating a tradition followed initially by other dynastic families, but also eventually by the cities themselves.
In ca 560 B.C. Sicyon dedicates the monopteros building. The upper part of it was adorned by a doric frieze with metopes and triglyphs. The sculptural decoration of this treasury is an excellent example of the renowned in antiquity archaic art of Sicyon, where painting with precise contours and details of forms dominates over sculpture. Parts of this frieze were discovered later in the foundations of the Treasury of the Sicyonians. As far as the initial use of the monopteros is concerned, it has been suggested that it served as a shelter for the chariot with which Cleisthenes won the chariot races of the Pythian Games of 582 B.C.
Next to the austere Doric structures built within the sanctuary of Delphi, the construction of which was ordered by the cities of mainland Greece, one finds the Treasury of the Siphnians which is dated to ca. 524 B.C. and represents the style of the eastern Greek islands and the rich in decoration Ionic order. Its architectural remains allow for its detailed portrayal. On the façade of the temple, instead of two columns in antae, the architrave was supported by two Caryatids, precursors to the Caryatids of the Erechtheion.
In the sacred space of Athena Pronaia, just before the dawn of the 5th c. B.C., the inhabitants of Massalia (Marseilles), the colony of the Phocaeans, dedicated a very elegant treasury with exceptional sculptural decoration, probably in order to express their gratitude to the goddess for their victory over the Ligurians.
In terms of the movable artefacts, the city of Argos was the first to devote identical oversized statues. This is the oldest monumental ex voto at Delphi and one of the early examples of  "great" Archaic sculpture bearing the signature of the sculptor Polymedes of Argos. They constitute a real couple, which is something rare in Greek art. Initially, they were identified as Kleobis and Biton, two strong and devoted brothers from Argos who carried their priestess mother to the temple of Hera by pulling her cart the entire way. However, according to recent research the two statues are identified with the Dioscuri whose cult was widespread in the Peloponnese.
At around 560 B.C. Naxos, the rich island of the Cyclades sent a magnificent offering to Apollo at Delphi. It is the statue of the mythical Sphinx whose colossal size, imposing form and place in the sanctuary (near Sibyl's rock) underlines the political and artistic prevalence of Naxos during the Archaic period. The demonic creature with the female face and enigmatic smile, the body of a lion and the feathers of a bird was set upon the capital of an extremely tall ionic column, which is considered the oldest example of Ionic order in Delphi. Its colossal size and height from which it controlled the Delphic landscape most likely provoked awe to the pilgrims of the Archaic period. 
From the same period come the renowned chryselephantine ex votos depicting Apollo, Artemis and Leto, nowadays in the Museum of Delphi. 
However, the most famous gifts which are described in detail by Herodotus (A, 51, 1-5) are the votive offerings of the Lydian King Croesus. These offerings comprised, among others, two oversized craters, a golden and a silver one, four silver pithoi (jars), two sprinklers, also a golden and a silver one, and a golden statue of a woman, which apparently depicted the  woman who used to knead Croesus' bread. Some of these offerings were destroyed during a fire, whereas those which were preserved were kept in the treasuries of the Clazomenians and the Corinthians. 
“When these offerings were ready, Croesus sent them to Delphi, with other gifts besides: namely, two very large bowls, one of gold and one of silver. The golden bowl stood to the right, the silver to the left of the temple entrance. [2] These too were removed about the time of the temple's burning, and now the golden bowl, which weighs eight and a half talents and twelve minae, is in the treasury of the Clazomenians, and the silver bowl at the corner of the forecourt of the temple. This bowl holds six hundred nine-gallon measures: for the Delphians use it for a mixing-bowl at the feast of the Divine Appearance. [3] It is said by the Delphians to be the work of Theodorus of Samos, and I agree with them, for it seems to me to be of no common workmanship. Moreover, Croesus sent four silver casks, which stand in the treasury of the Corinthians, and dedicated two sprinkling-vessels, one of gold, one of silver. The golden vessel bears the inscription “Given by the Lacedaemonians,” who claim it as their offering. But they are wrong, [4] for this, too, is Croesus' gift. The inscription was made by a certain Delphian, whose name I know but do not mention, out of his desire to please the Lacedaemonians. The figure of a boy, through whose hand the water runs, is indeed a Lacedaemonian gift; but they did not give either of the sprinkling-vessels. [5] Along with these Croesus sent, besides many other offerings of no great distinction, certain round basins of silver, and a female figure five feet high, which the Delphians assert to be the statue of the woman who was Croesus' baker. Moreover, he dedicated his own wife's necklaces and girdles”.

Text: Dr. Cleopatra Ferla, Historian
Translation: Dr.Metaxia Papageorgiou