As Charles Nicholas, Wojtkoski variously penciled and inked stories for Timely Comics, the 1940s predecessor of Marvel Comics, where his credits include the character The Defender in "USA Comics" #1 (Aug. 1941), and stories in "Young Allies Comics" #1 (Summer 1941), "Tough Kid Squad Comics" #1 (March 1942), and "Comedy Comics" (during 1942). Following World War II military service, he returned to Timely, where, beginning with comics cover-dated Spring 1946, he worked on a variety of stories and covers for "Captain America Comics", "Human Torch Comics", "Marvel Mystery Comics", "Sub-Mariner Comics" (where he drew the backup feature "Blonde Phantom"), and the landmark "All Winners Comics" #21 (Winter 1946/47), featuring Timely/Marvel's first superhero team, the (hyphenated) All-Winners Squad; Nicholas penciled the cover and the Miss America chapter, and inked penciler Al Avison's lead chapter.