"Gloria" is a song written by Northern Irish singer-songwriter Van Morrison and originally recorded by Morrison's band Them in 1964 and released as the B-side of "Baby, Please Don't Go". The song became a garage rock staple and a part of many rock bands' repertoires. It is particularly memorable for its "Glooooria!" chorus. It is easy to play, as a simple three-chord song, and thus is popular with those learning to play guitar.

Morrison said that he wrote "Gloria" while he performed with the Monarchs in Germany in the summer of 1963, at just about the time he turned 18 years old. He started to perform it at the Maritime Hotel when he returned to Belfast and joined up with the Gamblers to form the band Them. He would ad-lib lyrics as he performed, sometimes stretching the song to 15 or 20 minutes. After signing a contract with Dick Rowe and Decca, Them went to London for a recording session at Decca Three Studios in West Hampstead on 5 April 1964; "Gloria" was one of the seven songs recorded that day. Besides Morrison, present were Billy Harrison on guitar, Alan Henderson on bass, Ronnie Millings on drums and Patrick John McCauley on keyboards. Rowe brought in session musicians Arthur Greenslade on organ and Bobby Graham on drums, since he considered the Them members too inexperienced. There remains some dispute about whether Millings and McCauley were miked up, but Alan Henderson contends that Them constituted the first rock group to use two drummers on a recording. Although some sources claim that Jimmy Page played second guitar, other sources deny this.

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