Rai Kuniyuki was the founder of the Rai school, the third of the Yamashiro lines of swordmaking after the Awataguchi and that of Sanjo Munechika. Originating in the l3th century, the Rai school produced elegant blades of two distinct types, slender and wide, this tachi being an example of the latter. The typical Rai forging pattern was a tight itame. The most common hamon used by these smiths were choji or ko-midare, but almost always with nioi and ko-nie. Muneyaki or tempering along the back of the blade is another Rai characteristic, but because of the wide bo-hi and burnishing on the mune, it is difficult to ascertain its presence on this example.