The Liberal and Democratic Union was a political party formed by early South Australianliberals, as opposed to the conservatives. It was formed in 1906 when liberal party structures were becoming more solid. Its leader, Archibald Peake, stressed that the LDU represented 'something not so sharply set as Labourism, not so dull in its edge as conservatism'. But with Labor taking over the middle ground, Kingstonian liberals like Peake had to choose.
When PremierThomas Price died in 1909, Labor demanded it retain the premiership in their coalition, however Peake refused. Invited to form a ministry, he filled it with LDU members and became premier, treasurer and minister of education. The ministry survived with the parliamentary support of the Australasian National League (conservatives) and the Farmers' and Producers' Political Union, and in December was reconstructed to include members of both.
John Verran led Labor to its first majority government in 1910, causing the anti-Labor parties to merge and form the Liberal Union, with Peake as leader. All groups readily approved the merger, however the LDU was more hesitant. Peake persuaded a party conference that 'the day of the middle party is passed', and approved the merger by one vote.