Matsugasaki Park occupies the site of the Yonezawa Castle main enclosure, and at its center stands Matsugasaki Shrine, where Uesugi Kagekatsu, Naoe Kanetsugu, and the reforming lord Uesugi Yozan are enshrined. Kanetsugu's role in building the foundations of the domain through its most difficult years was honored by later generations, who enshrined him at this symbolic heart of the former castle. A statue of Kanetsugu also stands in the park, a focal point for those engaging with Yonezawa's history.

Yonezawa Castle, now Matsugasaki Park, was Date Masamune's birthplace in 1567 and his stronghold as he expanded across Oshu, defeating the Ashina clan at Aizu. After Toyotomi Hideyoshi confiscated much of his territory, Masamune later moved his base to Sendai. Following the Battle of Sekigahara, Uesugi Kagekatsu took over the castle.