The Three Lions were relentless from the opening whistle, racing into a 4-0 half-time lead before adding three more goals after the break to record their biggest-ever victory in the UEFA Nations League. England's official website described the result as a record Nations League victory.
Harry Kane and Bukayo Saka both scored twice, while Jude Bellingham, Anthony Gordon and Morgan Rogers were also on target as England delivered a devastating attacking display.
Kane opened the scoring in the eighth minute, before Bellingham doubled England's advantage in the 21st minute. Gordon then made it 3-0 in the 39th minute, with Saka adding a fourth just before half-time.
England continued their assault after the interval. Kane completed his brace in the 53rd minute, before Saka scored his second in the 68th minute. Rogers completed the rout three minutes from full time.
The result was particularly significant for Kane, who moved to 89 international goals for England in 124 appearances. The Bayern Munich striker is now just one appearance away from equalling Peter Shilton's record of 125 caps for the men's senior team.
Bellingham was also influential, scoring once and providing three assists in a dominant individual performance.
The victory moves England onto six points from three matches in UEFA Nations League Group A3, leaving them three points behind leaders Spain, who maintained their perfect record with a 3-1 victory over Czechia.
England had entered the match following a 2-0 victory over Czechia on 29 September, having previously suffered a 3-2 defeat to Spain at Wembley in their opening Group A3 fixture.
For Croatia, the heavy defeat represents a major setback in their bid to challenge for the top positions in the group. The hosts were unable to respond after England's early breakthrough and were ultimately overwhelmed by the Three Lions' pace, movement and attacking quality.
England will return to action on Tuesday, 6 October, when they host Czechia at Wembley Stadium.