Charles Rockwell Lanman was born in Norwich, Connecticut, the eighth of the nine children of Peter Lanman III and Catherine (Cook) Lanman on July 8, 1850. His mother died when he was three years old, and his aunt Abigail (Abby) Trumbull Lanman helped raise him. His Aunt Abby was an artist, and as one of two legatees of the estate of her great uncle American Revolutionary War artist John Trumbull, inherited many of Trumbull's Revolutionary War period paintings and sketches. At age ten, a young Charles Lanman read a copy of the Journal of the American Oriental Society containing a translation of a textbook of Hindu astronomy, which sparked his interest in Sanskrit. Lanman graduated from Yale College (Phi Beta Kappa) in 1871, was a graduate student there (1871–1873) studying Greek under James Hadley and Sanskrit under WD Whitney and eventually earning his doctorate at Yale in 1873. He also studied Sanskrit under Weber and Roth and philology under Georg Curtius and August Leskien in Germany (1873–1876).