At the beginning, Masahide OGASAWARA (a son of Muneyasu) of the Suzuoka-Ogasawara clan had a advantage, but after Masahide was murdered and the Suzuoka-Ogasawara clan went to ruin, there was a conflict between the Fuchu-Ogasawara clan and the Matsuo-Ogasawara clan, and after all, Nagamune OGASAWARA (a great-great-grandson of Machinaga) of the Fuchu-Ogasawara clan defeated the Matsuo-Ogasawara clan and unified the family, building the height of the Ogasawara clan.
当初は鈴岡小笠原氏の小笠原政秀（宗康の子）が優勢であったが、政秀が謀殺されて鈴岡小笠原氏が滅亡すると府中小笠原氏と松尾小笠原氏との争いになり、やがて府中小笠原氏の小笠原長棟（持長の玄孫）が松尾小笠原氏を破って一族を統一し、小笠原氏の最盛期を築き上げた。