He was born in the village of Blackrock, Cork in County Cork, Ireland on November 24, 1843, son of Eyre Coote Croker. He was taken to the United States by his parents when he was two years old. They boarded the Henry Clay in Cobh, County Cork and headed for the land of opportunity. There were significant differences between this family and the typical family leaving Ireland at that time. They were Protestant. They were not land tenants. Eyre Coote Croker owned an estate in Clonakilty in south west Cork. However, he was not a good manager. Within a short space of time, he was as poor as his tenants.
Ricard Croker married Beulah Benson Edmondson (1884-1957) in 1914 when he was 71 years old.
He died in 1922 in Ireland leaving a fortune estimated to $3–5 millions to his second wife, disinheriting the children. This resulted in a celebrated lawsuit in which the children unsuccessfully claimed that their father's second marriage was invalid for bigamy, in that their stepmother was at the relevant time married to another man. They were, however, unable to produce any credible evidence that the gentleman existed.
Croker's funeral drew some of Dublin's most eminent citizens.
Richard Croker was educated in the public schools of New York City, where he eventually became a member of Tammany Hall and active in its politics.
He was an alderman from 1868 to 1870, a coroner from 1873 to 1876. He moved to Harrison, New York by 1880, then he was the New York City Fire Commissioner in 1883 and 1887, and city Chamberlain from 1889 to 1890. After the fall of John Kelly he became the leader of Tammany Hall, and for some time almost completely controlled that organization. As head of Tammany, Croker received bribe money from the owners of brothels, saloons and illegal gambling dens. He survived Charles Henry Parkhurst's attacks on Tammany Hall corruption and became a wealthy man.
Croker's greatest political success was his bringing about the 1897 election of Robert A. Van Wyck as first mayor of the five-borough "greater" New York, and during van Wyck's administration Croker is popularly supposed to have dominated completely the government of the city. After Croker's failure to carry the city in the presidential election of 1900 and the defeat of his mayoralty candidate, Edward M. Shepard in 1901, he resigned from his position of leadership in Tammany and was succeeded by Lewis Nixon. He retired to a country life in England and Ireland.
Croker operated a stable of thoroughbred racehorses in the United States in partnership with Mike Dwyer. In January 1895 they sent a stable of horses to England under the care of trainer Hardy Campbell, Jr. and jockey Willie Simms. Following a dispute, the partnership was dissoved in May but Croker continued to race in England. In 1907 his horse Orby won Britain's most prestigious race, the Epsom Derby. Orby was ridden by American jockey John Reiff whose brother Lester had won the race in 1901. Croker was also the breeder of Orby's son Grand Parade who won the Derby in 1919.
Croker bought the first $5000 bulldog, Ch. Rodney Stone.
In another animal venture, Croker was the first person to pay $5000 for a bulldog, Champion Rodney Stone.