A 1584 stalemate in Kantō between the Hōjō and Satake-Utsunomiya alliance, notable for reportedly deploying over 8,000 matchlock guns—surpassing Nagashino.
Key Facts
- Duration
- 110 days (May–August 1584)
- Hōjō force estimate
- 3,500 cavalry
- Satake/Utsunomiya force estimate
- 3,000 cavalry
- Matchlock guns deployed (allied forces)
- Over 8,000 guns
- Peace treaty date
- August 27, 1584 (lunar July 22)
- Key defection
- Minagawa Hiroteru defected to Hōjō on August 20
By the Numbers
Location
Cause → Event → Consequence
The Later Hōjō clan sought to expand influence in northern Kantō by targeting Oyama Castle, while the Satake and Utsunomiya clans, allied with Toyotomi Hideyoshi, moved to counter Hōjō aggression and protect Koizumi Castle. Tensions in the region were further heightened by broader power struggles between Hideyoshi, Ieyasu, and competing daimyo networks across central and eastern Japan.
Between May and August 1584, Hōjō forces numbering around 3,500 cavalry faced a combined Satake-Utsunomiya army of roughly 3,000 at Numajiri, in the border area of Kozuke and Shimotsuke provinces. Neither side achieved a decisive battlefield victory; instead, both conducted supply-line disruptions, diplomatic maneuvering, and raids over approximately 110 days, reportedly deploying more than 8,000 matchlock firearms on the allied side.
The conflict ended with a peace treaty on August 27, 1584, restoring the regional status quo that had existed before earlier attacks on Koizumi Castle. The Hōjō withdrew the following day. The battle's diplomatic ripples may have influenced the concurrent Battle of Komaki-Nagakute, as Hōjō aggression prompted northern Kantō daimyo to seek Hideyoshi's support and contributed to tensions between Hideyoshi and Ieyasu.
Belligerents & Mobilization Analysis
Side A
1 belligerent
Kajiwara Masakage, Minagawa Hiroteru (defected to Hōjō).
Side B
2 belligerents