He then studied law under Franklin Pierce, Asa Fowler and Charles H. Peaslee and passed the bar in 1842.

[9] During his term the legislature failed to pass resolutions condemning the Missouri Compromise and the Kansas–Nebraska Act, evidence that New Hampshire was trending away from the Democratic Pierce and Baker and becoming increasingly antislavery.

[15][16] By now a resident of Des Moines, during the war he was praised for his efforts to recruit, equip and train soldiers for front line regiments, and to keep track of their service records, including enlistments, promotions, wounds, deaths, and discharges.

[17] In addition, at the end of the war, Baker was credited with acquiring from returning Iowa units captured Confederate regimental flags and other memorabilia, and arranging to have it preserved.

[18][19] In 1874 Baker took part in an effort to combat a massive grasshopper infestation in Northwestern Iowa, exposing himself out of doors in harsh weather including sleet, snow and high winds.