The Dates of Variously-shaped Shields

It seems necessary, by way of introduction, to say a few words on the circular convex shields used from very early times by our Saxon and Norman ancestors. These were of wood, with a central boss of bronze, and were sometimes of very large size; frequently, if we may judge from contemporaneous illuminations, as much as four feet in diameter. Across the inside of the boss a handle was fixed, and the shields, which were thus held out almost at arm's length, as represented in many ancient MSS., must have been most cumbersome.
It is hard to see how the sword or lance could have been conveniently used. The round shape must have interfered greatly with the view of one's opponent, and a bungler would inevitably slice pieces from off his own shield while attacking his enemy. Moreover, such shields must have been lightly made: we know exactly how the bosses were fastened with rivets through the shield, for they are constantly found in Anglo-Saxon grave mounds, and the wood is thus known to have been of some thickness. But we can obtain from contemporary writings many more particulars.