The 109th Infantry was an infantryregiment of the British Indian Army. The regiment traces its origins to 1768, when it was raised as the 5th Battalion, Bombay Sepoys.
After World War I the Indian government reformed the army moving from single- to multi-battalion regiments.[2] In 1922, the 109th Infantry became the 4th Battalion 4th Bombay Grenadiers. After independence it was one of the regiments allocated to the Indian Army.