"Johan Cruyff wanted to sign Thierry Henry for Barcelona when he was a young player. When I was elected president in 2003 I wanted to sign him, we also wanted to sign him last year and today it is a great pleasure to see him here."
"He is one of the best players in the world and given his quality, experience and commitment he comes to Barcelona at the perfect time."
Barcelona were denied a third straight Primera Liga title on the final day of the season a week ago, losing out to arch-rivals Real Madrid on head-to-head results.
A great deal of soul-searching has gone on since then after a season with no silverware, and the club has moved quickly to strengthen the squad and appease the fans.
Henry turned down a move to Barca and signed a four-year contract with Arsenal after they lost to Frank Rijkaard's team in the 2006 Champions League final in Paris and has described his move as the hardest decision of his life.
At Barca, Henry faces the prospect of having to find a place in the one of the most feared forward lines in European football, which includes Cameroon striker Samuel Eto'o, Brazil playmaker Ronaldinho and Argentina winger Lionel Messi.
Meanwhile his departure willl leave a huge void back in London and at Arsenal.
However some of the money generated by the sale of their captain could be invested in bringing back a former player.
Reports in the British media suggest manager Arsene Wenger could try and prise Nicolas Anelka from Bolton. The French striker starred for the Gunenrs in a brief spell as a teenager winning the domestic double in 1998.