Protestant Church in the Netherlands, united Christian church, largest Protestant church in the Netherlands, formed in the merger of three Dutch churches. In May 2004, after nearly 20 years of negotiations, the Reformed Churches in the Netherlands (Nederlands Gereformeerde Kerken; then the second largest Protestant church in the country), the Netherlands Reformed Church, and the Evangelical Lutheran Church in the Kingdom of the Netherlands merged to form the Protestant Church in the Netherlands. This church claimed about 2.5 million members in 2008.