A Methodist trained preacher and graduate of Wesleyan University, he also worked as a pastor across the country in the late 19th century, primarily in New England.

[2][4] His father was a merchant of English heritage who worked for the United States Customs in Boston and New Orleans, also acting as a clerk in Washington, D.C. for the Department of the Treasury.

[2] Whitaker moved on to college at Wesleyan University in Middletown, Connecticut, where he earned a Bachelor of Arts degree in 1861.

[6] Whitaker then started working as a pastor for the Methodist Episcopal church in West Medway, Massachusetts, in 1861 and remained until 1863.

[3][7] During this time, he continued his studies and earned a Master of Arts degree from Wesleyan in 1864, where his brother Nicholas also attended.

[9] During his tenure he clashed with the board of trustees, the students, and faculty over his old fashioned ways and made an attempt to gain full control over the university in 1893, threatening to resign.

[1][10] Following his tenure at Willamette, Whitaker moved to Portland, Oregon, where he was the pastor at St. Paul's Church in 1893, followed by the same position in Detroit, Michigan, from 1894 to 1896.

[5] In 1899, he was hired to be the president of Portland University, Willamette's financially failing rival, and where his son John Holland earned a degree.

[5] In civic affairs he was a member of the Republican Party, the Sons of Temperance, the Temple of Honor, the Evening Star, and a Freemason.