<P> The Baltimore Colts relocation to Indianapolis was a successful effort by the then - owner of the Baltimore Colts (Robert Irsay) to move the American football team from Baltimore, Maryland to Indianapolis, Indiana . The team began play as the Indianapolis Colts for the 1984 National Football League (NFL) season . The Colts' move was completely unannounced and occurred in the early hours of March 29, 1984, after years of lobbying for a new stadium to replace the inadequate Memorial Stadium . The franchise's move continues to embitter many Baltimore natives decades afterward, and would have a lasting impact on the NFL, including another controversial relocation twelve years later that resulted in Baltimore receiving its current NFL team, the Ravens . </P> <P> Although the Colts had been successful since arriving in Baltimore for the 1953 NFL season, Memorial Stadium was claimed to be "inadequate" for both them and Major League Baseball's Baltimore Orioles . In May 1969, the city of Baltimore announced it would seek a "substantial" increase in Memorial Stadium rental fees from Colts owner Carroll Rosenbloom and the team itself . Rosenbloom had already called Memorial Stadium "antiquated" and had threatened to move all Colts home games out of the stadium unless improvements were made . Rosenbloom even considered using $12--20 million of his own money to help fund the building of a new football only stadium on land in adjoining Baltimore County . By November 1971, Rosenbloom announced that the Colts would not return to Memorial Stadium when their lease ran out following the 1972 season and that he was not interested in negotiating with the city anymore . He wanted out of Baltimore for a few reasons--team revenue, problems with Baltimore Orioles ownership relating to Memorial Stadium revenues, a running feud with the Baltimore press, and his new wife's desire to move to the West Coast . Real estate investor Will Keland was originally slated to buy the Colts from Rosenbloom . Keland could not generate enough funds necessary to purchase the team, but his golfing buddy Robert Irsay, who originally was only slated to own 1 percent of the team, did possess the necessary funds and moved in to make the purchase . On July 13, 1972, Irsay became owner of the Colts . Under the terms of the arrangement, he bought the Los Angeles Rams for $19 million, then traded them to Rosenbloom for the Colts and $3 million in cash . </P>

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