“Happy Xmas (War Is Over)” was the culmination of more than two years of peace activism undertaken by John Lennon and Yoko Ono that began with the bed-ins they convened in March and May 1969, the first of which took place during their honeymoon. The song’s direct antecedent was an international multimedia campaign launched by the couple in December 1969 that primarily consisted of renting billboard space in 12 major cities around the world for the display of black-and-white posters that declared “WAR IS OVER! If You Want It – Happy Christmas from John & Yoko.” The track had a delayed release in late November of 1971 which gave it very little promotional time and airplay heading into the Christmas season, but was a hit in 1972 as promotion and airplay ramped up at just the right time, including promotional shirts, most of which were single sided with the War Is Over message in green ink, though there were also some that were two sided with the Happy Christmas message on the back in green plus black and white inks.