The Three Lions had a bit of revenge over the side that knocked them out of the 2018 World Cup semi-final in Russia to go ahead in Group D.
England started on the front foot but lacked the cutting-edge to worry Zlatko Dalic’s men as they managed to get only one shot on target out of their four attempts before the interval.
The Englishmen resumed the second half in similar fashion and got their reward twelve minutes later after Leeds United midfielder Kalvin Philips dribbled past two players before teeing up Raheem Sterling, who hit the ball past the rushing Dominik Livakovic.
"I'm most pleased with the performance. Of course the win is important. To win the first game relieves some tension but it doesn't mean we've qualified and that's the first objective,” Southgate said.
"The performance was really good. It was a big occasion, a sweltering hot day and the players settled really quickly, used the ball well and we limited Croatia to very few clear chances throughout the game.
"They are a good opponent who we have huge respect for and we know so much about so I couldn't be happier with not just the players that started but those who came in and the whole group for the way they prepared for this game.
"Firstly, it's a lovely day for the English public. We've waited a long time for the beer gardens to open and I'm sure they're throwing it everywhere as well as drinking it which is lovely!
"But for us, it relieves some tension. You know if you don't win the first game, the pressure ramps up. But we have two really difficult games left in this group and we're a good step forward today but important steps to go to qualify."
