 The state constitution was sent to the United States Congress for ratification in December 1857 . The approval process was drawn out for several months while Congress debated over issues that had stemmed from the Kansas @-@ Nebraska Act . Southerners had been arguing that the next state should be pro @-@ slavery , so when Kansas submitted the pro @-@ slavery Lecompton Constitution , the Minnesota statehood bill was delayed . After that , Northerners feared that Minnesota 's Democratic delegation would support slavery in Kansas . Finally , after the Kansas question was settled and after Congress decided how many representatives Minnesota would get in the House of Representatives , the bill passed . The eastern half of the Minnesota Territory , under the boundaries defined by Henry Mower Rice , became the country 's 32nd state on May 11 , 1858 . The western part remained unorganized until its incorporation into the Dakota Territory on March 2 , 1861 . 
