Social Democratic Party of Yamatai

The Social Democratic Party of Yamatai (山都社会民主党; SDP), sometimes abbreviated to Shamin-tō (社民党), is a centre-left political party in Yamatai. The party was founded in June 2003 as a split from the Democratic Party of Yamatai following the Mizuno Land Scandal and the resignation of Watanabe Tadao. In late 2016, the party absorbed the New Environmental Party. As of 2021, the SDP is considered the primary opposition party in Yamatai and is the second-largest party in the Teikoku Gikai behind the ruling Yamatai Restoration Party. The party is currently led by Nakanishi Shichiro.

History
Following the Mizuno Land Scandal in 2003, where Minister of Land Itaya Kaiichi was indicted on charges of corruption and ties to the Gokudo, the Democratic Party split into two factions. The majority of the party members sought to reform the party and distance themselves from Itaya and the scandal, largely rallying behind veteran party member Uemura Takayuki. The Morimoto faction, which was a core group of senior party members under Morimoto Nori, was opposed to major party reforms and sought to maintain cohesion to face the upcoming elections that would follow the impending resignation of party leader and then-Prime Minister Watanabe Tadao.

Uemura's faction largely believed that the DPY already had no chance to win the upcoming election due to the high levels of public outrage, but Uemura acquiesced to Morimoto's request to avoid splitting the party until after the election, which was held on 22 June with a landslide YRP victory. On 24 June 2003, the SDP was formed at a press conference.

During the 2007 general election, it was announced that the SDP would not contest seats where the DPY was was running, a gesture which was not returned by the DPY. Nonetheless, the SDP won a total of 84 seats, becoming the leading opposition party at the time.

In October 2016, the SDP carried out a merger with the New Environmental Party of Yamatai as well as some independent Gikai members.

During the 2019 general election, the SDP formed a coalition with the DPY and the left-wing populist Let's Save Yamatai Party, and secured 154 seats in the Gikai, the largest number since the 2003 loss.

Ideology
The party supports a decrease in the consumption tax as well as higher taxes on corporations and wealthy individuals, and an increase in support for the agricultural sector. The SDP is against an increase in the defence budget and further overseas interventions, as well as the legalisation and maintenance of casinos.

The SDP also supports environmentalism, and seeks increased government investment in renewable energy, as well as an eventual phasing out of Yamatai's high reliance on nuclear energy and fossil fuels. In the education sector, the SDP supports education reform to reduce high stress amongst children in Yamatai.

The party supports LGBT rights and the legalization of same-sex marriage in Yamatai.