From Muppet Wiki

Queen Elizabeth II (b. 1926), full name Elizabeth Alexandra Mary, is the Queen of England (and the United Kingdom as a whole and fourteen other states/territories) and has reigned since 1952. Her Majesty takes an active interest in affairs of state, but more often avoids politics and takes a primarily ceremonial role. One example is her attendance at the Royal Variety Performance. At the conclusion of the 1977 performance, she personally congratulated Jim Henson and his puppeteers.

Decades later, Kermit the Frog was one of the many celebrities paying their respects during the Golden Jubilee celebrating her fiftieth year on the throne.

References

• In the seventh season Muppet Babies episode "Happy Birthday, Uncle Piggy," Baby Piggy's fantasy party plans for Uncle Statler include heads of state as guests. A cut-out of Queen Elizabeth appears (voiced by Frank Welker) to add her congratulations.

• In Muppets Tonight episode 103, Her Majesty (played by an uncredited impersonator) appears as part of The Billy Crystal Band with fellow lookalikes Ronald Reagan, Bill Clinton, Clint Eastwood, and Boris Yeltsin. She uses her feminine charms on Bobo in order to gain admission into the studio, but the bear is appalled by her flirtation and sends her to the back of the line.