Count Alexander Ivanovich Rumyantsev (Russian: Александр Иванович Румянцев) (1677–1749) was an assistant of Peter the Great and father of Field Marshal Peter Rumyantsev-Zadunaisky. He came from the Rumyantsev family which, though little known and documented in the 17th century, later claimed descent from a prominent 14th-century boyar.
Alexander enrolled in the Preobrazhensky regiment of guards in 1704. While he guarded the headquarters of Peter the Great, the monarch noticed him "for his great height and smart face". Peter made Alexander Ivanovich his servant and later recommended him to Peter Shafirov and Peter Tolstoy. In the service of these two courtiers, Rumyantsev led a mission to capture hetman Pavlo Polubotok and carried out various diplomatic errands in Constantinople and in Persia.
In 1720 he married the daughter and heiress of Count Andrey Matveyev, Countess Maria Matveyeva, who was rumored to have been intimate with the Tsar. His wife survived him by 40 years, and entertained Saint Petersburg society with the stories of her acquaintance with Louis XIV, Madame de Maintenon, and the Duke of Marlborough. When she died at the age of 90, Gavrila Derzhavin wrote a remarkable ode glorifying her virtues.