At age 15, he emigrated with his family to Texas with the Adelsverein settlers, disembarking at Galveston on December 18, 1845, from the Johann Detthard .

Leopold von Iwonski sold his 320-acre land grant and moved the family across the Guadalupe River from New Braunfels, to a settlement which came to be known as Neighborsville.

[5] Iwonski began making sketches of troops stationed in the south Texas area during the Civil War.

During Reconstruction, Carl von Iwonski became San Antonio city tax collector, and his father Leopold became Bexar County treasurer.

Both father and son become radical leaders in the local Republican party, and Carl began to draw political cartoons.