Here’s an English Civil War variant of the Command and Colors rules. You’ll also need the Command and Colors: Napoleonics rules, which are freely available on the GMT Games website.
English Ciivil War
D3 ECW Rules
A variant of the One-Hour Wargames rules, the D3 ECW rules use a combination of D3 (1,1,2,2,3,3) and D6 dice.
Rupert’s Very Bad Day: Battle of Marston Moor
The Junior General offers a set of rules for the English Civil War battle of Marston Moor.