Thiago brought an end to a seven-year stay at the Allianz Arena where he won sixteen trophies which includes seven Bundesliga titles and one Champions League trophy.
The 29-year-old becomes Liverpool’s second signing of the summer, after the arrival of Greece defender Kostas Tsimikas from Olympiacos.
The Spain international has signed a four-year deal that will keep him at Anfield until the summer of 2024 and will be wearing the no.6 jersey.
“I think it’s an amazing feeling. I was waiting for this moment for a long time and I am very, very happy to be here," Thiago said in a statement.
“When the years are passing, you are trying to win as much as you can – and when you win, you want to win more. I think this club describes what I am as well; I want to achieve all of the goals, win as many trophies as possible.
“It also [has] this kind of family [feeling] that I need because we [like to] have a very close relationship with the club and I think I will feel this, I will have this feeling, with this club as well.”
He added: “I must adapt to the team as fast as I can in the situation and the context that we are living right now.
“Everything is more compact and we started a little bit later, but still it is football and I think we have to mix all the big things up, all the good things we have. I will help the team in a defensive and offensive [way] and also in a mental aspect.
“[The fans] are not more excited than I am, for sure not! It is not about saying words, it is about doing the things. I will give my heart on the field to my teammates, the club and also to the fans.”