He held considerable influence in Tammany Hall for twenty-five years and was credited for delivering New York to James K. Polk and securing his election as President of the United States.
[3] Born to a German-American father and an Irish Protestant mother,[4] Rynders first appeared in New York City during the mid-1830s, after a brief career as a professional gambler and pistol-and-knife fighter on the Mississippi River, and soon became involved in local politics.
Owner of at least half a dozen green-groceries in Paradise Square, he was able to win the predominantly Irish-American gangs to the cause of Tammany Hall and organize them into a voting block.
[4] By the end of the decade, he was considered to be the de facto leader of the Five Points street gangs and was often requested by authorities to use his influence to cease rioting and gang-related violence which the police were unable to stop.
[7] On one occasion, the famous abolitionist Wendell Phillips was stopped from speaking at the Broadway Tabernacle when Rynders, a proponent of slavery, publicly threatened that he and his men would "wreck the building and mob the audience".
[3] This decision would lead to his downfall as the political boss of the Sixth Ward when, during the Dead Rabbits Riot in 1857, he was attacked and pelted with rocks while attempting to persuade the warring gangsters to cease fighting.
[4][10] Rynders remained in politics, attending the 1860 Democratic National Convention as a regular member of the New York delegation [11][12] In early 1861, he was ordered by Chairman Morris to find William Hepburn Russell and return him to Washington, D.C. but telegraphed the capitol on March 2 that he was unable to locate him.