What is the oldest current government in the world?

The United Stated of America holds claim to the oldest current national government in the world..

Actually, the oldest government is the government of San Marino, a European microstate within Italy. The San Marino Constitution was adopted in 1600, about 180 years prior to the United States' formal creation of its current government in 1789.

Sorry but from 1923 to 1943, San Marino was under the rule of the Sammarinese Fascist Party. That constitutes a break in the Government and means the San Marino is not the oldest government in the world.

Even if they went back to the same type and form of government with the exact same constitution it is still 3 separate governments.

The Isle of Man's Tynwald Government has been running since 1417. By far the longest running government in the world, a fact recognised by the guiness book of records.