The discovery of gold in Australia in 1851 caused not only immigration of a non-agricultural class of workers but also the enactment of severe laws against miners: expensive monthly licenses (regardless of mining success) and frequent inspections -- both a form of economic and social control. Disenfranchised, the miners used protests to show their unhappiness with the restrictions, one demonstration so tumultuous that troops were called up. Leaders experienced in Welsh and English Chartism caused a mass movement for universal suffrage, but the Australian government acted only when miners burned licenses, and then it sent troops. In December 1854, miners in the Eureka goldfield organized themselves into military units, erected a stockade, and, though poorly armed, manned it against government troops. Some 400 troops assaulted the stockade, guarded by 150 miners; 30 persons were killed in the clash, which ended with a rout of the miners. Then the troops terrorized miners in their tents, killing a few and injuring many. But their efforts merely reinforced the demand for social change. The severe Australian laws that prompted the Eureka Stockade Miner's Rebellion were finally modified in 1854.