The 25-year-old Chester-born centre-back, who is in the squad for the Three Lions' friendly against Sweden tonight, could have competed for the Welsh side because he grew up in North Wales.
"When I was a schoolboy, I played for Wales because I went to school in Wales," Wales Online quotes Shawcross as saying. "But when I turned 16, there was a rule that said I couldn't play for Wales.
"In recent months, that rule changed and I could play for Wales again. But I decided years ago I wanted to play for England and I spoke to Chris Coleman, and Gary Speed before that, and made it clear that I wanted to play for England."
Shawcross was called into the England squad for the first time last month when he was picked for the side's 2014 World Cup qualifiers against San Marino and Poland.