Simplify the following text for a Grade 9 native English-speaking person.
Original: Soundgarden supported Ultramega OK with a tour in the United States in the spring of 1989 and a tour in Europe , which began in May 1989 and was the band 's first overseas tour .
Simplified: Soundgarden supported Ultramega OK with a tour of the United States in the spring of 1989 and a tour of Europe which began in May 1989 and which was the band 's first overseas tour .