Why did Pericles support a law requiring Athenian parentage on both sides for citizenship?

In 451 or 450 BCE, Pericles introduced a law restricting Athenian citizenship to individuals with Athenian parentage on both sides. Historical sources do not provide definitive background for this proposal, leading to several scholarly interpretations regarding his motivations:1

• Political Strategy: Some argue the law was a tactical weapon used against his political rival, Cimon, who had a foreign mother.1
• Social Exclusivity: Pericles may have been championing the preferences of the lower classes, who were more inclined than the upper classes to support exclusionary policies against immigrants to preserve the fabric of Athenian society.1
• Resource Protection: The law may have reflected a general desire to limit access to the benefits of public office and state distributions.1
• Economic Security: Later orators suggested the law helped protect the status of Athenian women, ensuring that even the poorest girls possessed a valuable dowry in the form of their citizenship.1

While the law had a clear demagogic nature, it did not aim to restrict the economic opportunities of foreigners, who continued to play vital roles in the Athenian economy and military.1