When was the country Jordan founded?

In 1922, the area that included modern Jordan was established called the Emirate of Transjordan. (It was semi-autonomous.)

In 1946 on May 25th it became the independent Hashemite Kingdom of Transjordan. In 1950, the country was renamed the Hashemite Kingdom of Jordan .

A link is provided to the U.S. State Department web page on Jordan.