Brickwall will not fall

Charles John Mickelson
my friend's paternal grandfather
Birth 2 Apr 1875 in Finland
Death 16 Sep 1941 in Bronx, New York, USA

No records of where was his birth is known.
According to 1910 census he came to America in 1891.
In 1899 he was living in New Haven, Connecticut from where he entered the military in 1899 29 Sep Age: 24 and traveled to San Francisco, San Francisco, California, USA
The 27th Infantry U.S.V. traveled by train to the West Coast for shipment overseas. Left San Francisco at 8 a.m. on September 29, 1899, aboard the transport Tacoma, which arrived at Manila on October 27, 1899.
By 1904 he was living in Bronx, New York where he married Amanda Carolina Johnson. His death certificate gives only Finland as place of birth.
Any helped would be appreciated,
Peter