Strootman was given the Number 6 jersey, which was brought out of retirement after consultation with Roma legend Aldair.
"It's true I received other proposals, but I chose Roma because they are a great club on the world stage," said the 23-year-old Dutch international.
"I spoke to Coach Rudi Garcia and he is very important for me. I took everything into account and that made my choice easy.
"I can take on any midfield role, as I have both attacking and defensive characteristics. I like to help the team where I am needed most.
"I haven't spoken to Daniele De Rossi yet, but it will be an honour for me to play alongside this great champion. I hope he will stay, as we can co-exist.
"Victory is the objective and this is an important challenge after two difficult years for Roma. I will give 100 per cent.
"I am well aware that Roma paid a lot for me, but that must not affect my performances," said Strootman when asked about the pressure.
"I will learn Italian as soon as possible and hope to live up to expectations. I will be able to handle the pressure. I am here to win straight away and I know Serie A is a difficult League, but the new Coach is bringing in enthusiasm."