Another historian here. My chapter structure was outlined in the last paragraph of my intro i.e.

"The chapters which follow are organized thematically. Chapter 2 addresses the issue of ***. Chapter 3 looks at how ***. Chapter 4 considers what people ***. Chapter 5 develops this to consider the manner in which people were ***. Chapter 6 investigates the relationship between ***. Finally Chapter 7 pulls the threads together to present overall conclusions of the thesis to the core questions."

My main chapters didn't roll automatically from one to the other, but were more like segments of an orange, each looking at a different aspect of my research topic. Then chapter 7 was the big sum-up.

Thank you fellow historians - yes, I shall follow those phrases of introducing chapters. I hate being so explicit about things but know that it needs to be done to clearly guide the examiners and readers. Thanks.