Complex sentence: In particular, Elton was opposed to the idea that the English Civil War was caused by socio-economic changes in the 16th-17th centuries, arguing instead that it was due largely to the incompetence of the Stuart kings.
Split into simpler sentences: In particular, Elton was opposed to the idea that the English Civil War was caused by socio-economic changes in the 16th-17th centuries. Elton argued instead that the Civil War was largely due to the incompetence of the Stuart kings.