…Argos concludes a thirty years' peace with…

The disastrous end to the adventure in Egypt in 454 BCE has made Athens ready for a truce, and in 451 BCE Athens comes to terms with Sparta, while …

Wealthy Athenians possess land on the Lelantine Plain in the middle of the century.

As landowning is normally restricted to nationals of the state in which the land is situated, such ownership by individual wealthy Athenians of land in the subject cities of the empire is a telling phenomenon, because the land is usually acquired in defiance of local rules.

For Athenians to acquire such land, otherwise than by inheritance as a result of marriage to a non-Athenian, is an abuse.

Inheritance of this kind is much less likely after a law of 451 restricting Athenian citizenship to persons of citizen descent on both sides.

“Mixed marriages” after 451 must be far less common.

Pericles may intend this law as a low-level political weapon for use against Cimon, who has a foreign mother.

While the upper classes certainly have no prejudice against foreign marriages, the lower classes may well have more.

Possibly, Pericles here is championing exclusivist tendencies against immigrants who might break down the fabric of Athenian society.

Cimon, recalled to Athens, negotiates the Five Years' Truce with Sparta around the same time, ending hostilities among the Greek states.

Cimon receives permission to lead a big, new naval expedition against Persia, despite the disastrous failure of the previous Greek enterprise in Egypt (459-454).

He takes two hundred ships to Cyprus in 450, detaching sixty to help the Egyptian nationalists.

He defeats the Persians at Salamis and recovers most of Cyprus, but dies of sickness or a wound at the siege of the Phoenician city of Citium (present Larnarca).

Cyprus throughout the fifth century will remain under Persian rule.

Hippodamus of Miletos uses the rectilinear grid system in planning the Athenian port of Piraeus around 450 BCE.

Cimon's death makes diplomacy imperative in the eastern sphere.

Apparently, a peace with Athens, advantageous to Persia, is signed in 449 BCE, whereby the Persians agree to stay out of the Aegean and the Athenians agree to leave Asia Minor to the Achaemenids.

The diplomat Callias, a notable member of one of the wealthiest Athenian families, who is said to have distinguished himself in the Greek victory over the invading Persians at Marathon and to have won the chariot race at the Olympic games three times, negotiates this so-called Peace of Callias (mentioned by Diodorus but one of Thucydides' most famous omissions).

Pericles now embarks on a policy designed to secure Athens' cultural and political leadership in Greece.

If peace with Persia has not ended the alliance of the Delian league, it may have ended the annual tribute paid to its treasury, transferred in 454 from Delos to Athens.

Whether to regain this tribute, or simply to assert Athenian leadership, Pericles summons a conference of all Greek states to consider the questions of rebuilding the Greek temples destroyed by the Persians, the payment of sacrifices due to the gods for salvation, and the freedom of the seas.

Sparta will not cooperate, but Pericles continues on the narrower basis of the Athenian alliance.

Tribute is to continue, and Athens will draw heavily on the reserves of the alliance for a magnificent building program centered on the Acropolis.

The architect Callicrates in 449 BCE designs the Temple of Athena Nike on the Athenian Acropolis.

Stylistic grounds are the basis for the theory that Callicrates may be the designer of the Illissos Temple completed around the same time.

Thucydides, son of Melesias (not the historian) and a relative of Cimon, who had inherited some of his political support among conservatives, denounces both the extravagance of Pericles' building project and the immorality of using allied funds to finance it.

Pericles argues that the allies are paying for their defense, and, if that is assured, Athens does not have to account for how the money is actually spent.

In addition to domestic criticism, there is also some initial allied resentment at the continuation of tribute, and some scattered revolts.

Pericles meets the situation in part by extending a network of Athenian settlements throughout what may now be called the empire, thus strengthening Athenian control and providing new land for the growing Athenian population.

Phocians, claiming the right to administer the shrine of Apollo, had taken control of Delphi by 450 BCE; the Amphictyonic League, with which Athens has made an alliance, protests that control of both the city and shrine rightfully belongs to them.

Sparta, entering for the first time into the concern of the league in 449 BCE, sends troops to expel the Phocians, who apparently depart without resistance, but Pericles dispatches Athenian troops to reinstate them.

Athens, a league member, then signs a treaty with Sparta, a unilateral action that angers the other members.

The Thebans rebel, unchallenged by Athens, and the Phocians, their alliance to Athens no longer in effect, retain control of Delphi.

An unstable peace in 448 BCE ends this so-called Second Sacred War.

Pericles, in establishing one of the new Athenian colonies, engages in his most admired campaign, the expulsion of barbarians from the Thracian Chersonese (Gallipoli), to which he sends one thousand additional settlers (cleruchs) in about 448 BCE.

Eyewitness accounts written by Herodotus, who is the principal source for much of the history of this and previous ages, indicate that he traveled in Egypt probably sometime after 454 BCE or possibly earlier in association with Athenians, after an Athenian fleet had assisted the uprising against Persian rule in 460-454 BCE.

He probably traveled to Tyre next and then down the Euphrates to Babylon.

For some reason, probably associated with local politics, he subsequently found himself unpopular in his native Halicarnassus and migrated sometime around 447 BCE, to Periclean Athens, a city for whose people and democratic institutions he declares his open admiration (V, 78) and where he come to know not just leading citizens such as the Alcmaeonids, a clan whose history features frequently in his writing, but also the local topography (VI, 137; VIII, 52-5).

According to Eusebius and Plutarch, Herodotus was granted a financial reward by the Athenian assembly in recognition of his work and there may be some truth in this.

It is possible that he applied for Athenian citizenship—a rare honor after 451 BCE, requiring two separate votes by a well-attended assembly—but was unsuccessful.

Herodotus is the first to use the term “delta” (from the Greek letter) in referring to the triangular alluvial deposits at the mouth of the Nile River.

Callicrates, together with fellow architect Ictinus, begins supervising the construction of the Parthenon on the Athens Acropolis in 447, a project entrusted to them by Pericles.

Phidias begins work on the gold and ivory statue of Athena that the Parthenon is to house.

The Acropolis project is to include, among other things, a temple to Victory and the Propylaea (started 437), the entrance gateway, far grander and more expensive than any previous Greek secular building.