Final answer:
No U.S. president has been impeached due to direct links with the Russian Mafia. Donald Trump was impeached on charges related to Russian matters. Other impeached presidents include Andrew Johnson, while Richard Nixon resigned before impeachment, and Bill Clinton was impeached for different reasons.
Step-by-step explanation:
The president that was impeached because of his links with Russian matters, although not specifically the Russian Mafia, was Donald Trump. His first impeachment involved accusations of misuse of power and obstruction of Congress in relation to allegations that he sought help from Ukrainian officials, which could have involved Russian interests as part of electoral meddling concerns. However, it's important to note that no U.S. president has been impeached due to direct links with the Russian Mafia. The most well-known case of impeachment connected to misconduct relating to Russia was the investigation into potential collusion between Trump's election campaign and Russian entities. In the history of U.S. presidencies, other presidents who have been impeached include Andrew Johnson, who was impeached in 1868, Richard Nixon, who resigned before he could be impeached in 1974, and Bill Clinton, who was impeached in 1998 over perjury and obstruction of justice charges relating to an extramarital affair.