Jaakko Pentinpoika Ilkka (1545, Ilmajoki – January 27, 1597) was a Finnish yeoman and trader. He is remembered for leading the Cudgel War of 1596; at its end, and the peasants' defeat on January 1–2, 1597, he escaped, but was soon recaptured and executed for his part in the fighting.
- "The Descendants of Jaakko Ilkka - A Family History". nic.fi.
- "Family Tree DNA - N Y-DNA Haplogroup Project". familytreedna.com.
- "Jaakko NN Ilkka". geni.com.