The empire crumbled when the ruler's indiscretions came to light.
2
To break into crumbs.
We crumbled some bread into the water.
3
To mix (ingredients such as flour and butter) in such a way as to form crumbs.
Using your fingers, crumble the ingredients with the fingertips, lifting in an upward motion, until the mixture is sandy and resembles large breadcrumbs.