Circumstantial evidence from Emigration and church records proves that the Rosengren family came to Utah between 1861 and 1866. They sailed to America in 1861 on the ship Monarch of the Sea, arriving in New York 16 June 1861. The first documentation to confirm their arrival in Utah is the payment of tithing by Jons in Ephraim, Utah in 1866. Further research is needed to determine the year they came to Utah and the name of the pioneer company they traveled with.
His birth and death dates are confirmed by the inscription on his gravestone. A secondary source gives his birth date as 30 July 1812, but a primary source is needed to confirm this information.