Peter Hayes Sawyer was an English historian. His work on the Vikings was highly influential, as was his scholarship on Medieval England. Sawyer's early work The Age of the Vikings argued that the Vikings were "traders not raiders", overturning the previously held view that the Vikings' voyages were only focused on destruction and pillaging.
Sawyer is particularly known for his annotated catalogue of Anglo-Saxon charters. Anglo-Saxon charters are referenced by "Sawyer" numbers (abbreviated 'S' as for example in charter "S 407") according to his catalogue.
Anglo-Saxon Lincolnshire is an area that is both firmly fixed, but at the same time also a tad obscure. Most people know where it is, who owned it at the key dates and how it related to the whole. However, it's a wise bean who can confidently name more than three people from the county without having to put some thought into it.
This book begins with comments upon the evidence, the shire and its resources and then it takes you from the end of Roman rule up to the end of the reign of William I. There are digressions into the church and the local economy and the appendices flesh out some of the evidence (burials, coin finds, Tribal Hidage, etc).
This is a well written book and it's not a difficult read. As Lincs was mostly a political backwater a fair bit of the book talks about things in the greater realm and the connections to the county, as opposed to events originating there.
Three things that you will take away from this book:
1, Lincolnshire isn't the same as Lindsey – Kestevan was part of Middle Anglia and separate for a large part of the book, Holland was marsh and water and the area around Lincoln didn't have much to do with the villages on the coast.
2, how wealthy the place was. Coin finds, trade and the output of the mints (all linked), made this a very wealthy county.
3, the strong connections between Lindsey and Deira/York. These aren't just within the age of Northumbrian supremacy, but resumed in the Viking age and are most interesting.