Ishin no To (Japan Innovation Party) may have marked a quick restart under its new leader Yorihisa Matsuno following the exit of its two co-founders — Toru Hashimoto, who said he would retire from politics at the end of his term as Osaka mayor in December, and Kenji Eda, who resigned as party chief following the rejection of Hashimoto's bid to reorganize the city of Osaka in the May 17 referendum. But the main task ahead for the second-largest opposition force — which has relied heavily on Hashimoto's popularity and strong personality — will be to establish a clear identity as a political party.

The party has its roots in the Osaka Ishin no Kai — a local political group launched by Hashimoto and his allies in 2010 to carry out Hashimoto's agenda of Osaka's administrative reorganization. In 2012, Diet members who formerly belonged to other parties including the Democratic Party of Japan, the Liberal Democratic Party and the now-defunct Your Party joined forces with this group to create the national party Nippon Ishin no Kai as the Lower House election loomed. The lawmakers were clearly drawn to the popularity of Hashimoto and the Ishin brand as a boost to their chances in the December 2012 election, which indeed propelled Nippon Ishin to the third-largest party in the lower chamber, closely trailing the DPJ.

But the amalgam of lawmakers from different backgrounds suffered from a lack of clear identity as a national-level political force. For better or worse, the party's fortunes depended on those of Hashimoto, and members were divided by key differences on policy issues. Last year, conservative members led by former Tokyo Gov. Shintaro Ishihara split from the party due to differences over a realignment with other opposition parties.