Having been under successive control of the Dukes of Burgundy, the Habsburg Empire, and the Kingdom of Spain, the Netherlands effectively achieved independence in 1581. Dutch sovereignty was later codified in the Treaty of Münster, signed in 1648. Following a period of Napoleonic rule, beginning in 1795, the Dutch reasserted their independence in 1813. A constitutional monarchy was installed together with a strong States-General (parliament), effectively laying the foundations for the present political system. The Constitution was revised in 1848 giving greater power to the States-General and has existed almost unchanged since that time. Within the present system, the role of the monarch is largely ceremonial; power rests mainly with the bicameral States-General and through it the government. The 150-member Second Chamber of the States-General is directly elected and is the more powerful of the two houses, having the ability to propose and amend legislation. In comparison, the First Chamber, which consists of 75 members elected by the 12 provincial councils, can only approve or reject legislation. Elections for both the First and Second Chamber are held every four years, though never in the same year. The government is usually formed by the largest party in the parliament, which either on its own, or through forming a coalition, controls a majority of votes in both chambers. In reality, no single party since World War II has been able to obtain an absolute majority; all postwar governments have been the products of various coalitions.
The electoral system is based on the principle of proportional representation, which ensures that each party in parliament receives an amount of seats roughly proportional to its share of the national vote. Thus, if a candidate in a given district is defeated, his votes are not lost but are added to a pool that will then determine the distribution of seats in a second round of allocation. This system, unlike the "first past the post" voting practiced in countries such as the United States, makes it much easier for smaller parties to gain representation. Since the election of 6 May 1998, the Second Chamber has contained representatives of nine separate parties.
For more than half a century, starting in 1917, Dutch politics was dominated by political parties closely tied to the two major religious denominations, Roman Catholic and Protestant. These religious-based parties, either alone or in coalition, participated in each government that was formed. In 1980, a number of these parties merged to create the Christian Democratic Appeal (CDA) Party, which went on to form successive governments until being removed from power after the election of 4 May 1994. That election, which resulted in a coalition government under the leadership of Wim Kok and his Labor Party (PvdA), marked the first time since World War I that the traditional religious parties had been excluded from power. This situation was confirmed by the May 1998 election, from which the PvdA emerged as the largest party, with 45 seats. As was the case in 1994, Kok again chose to form a so-called "purple" coalition with the People's Party for Freedom and Democracy (Liberal Party—VVD) and a smaller center-left party named Democrats 66 (D-66), again excluding the CDA. The term "purple" in this case describes a melding of the three parties' colors—red for the PvdA, blue and orange for the VVD, and green for D-66.
In April 2002, the coalition resigned in the wake of a damning report on the failures of the detachment of Dutch peacekeepers to protect the safe haven of Srebrenica in Bosnia. Dutch soldiers were supposed to guarantee the safety of the local residents, yet failed to prevent Bosnian Serbs from taking over the safe haven and massacring over 7,000 Muslim men and boys in 1995. The report condemned both the United Nations (UN) and Dutch politicians for lack of foresight and preparation. In response, the entire Kok cabinet resigned six weeks before scheduled elections, to take responsibility for the mistakes of the ill-conceived UN mission. The May 2002 election brought much excitement and uncertainty. A totally unknown former academic, Pim Fortuyn, created a new political party, called List Pim Fortuyn (LPF), that ran on a platform of deregulation and privatization in combination with anti-immigrant, anti-Islamic slogans. Although a lone gunman assassinated Fortuyn on 6 May, nine days before the election, his party, which had not existed three months earlier, became the second-largest party in Parliament, holding 26 seats. The PvdA lost nearly half of its seats, going from 45 to 23. After some haggling and negotiations, the new government consisted, therefore, of the CDA, the new LPF, and the VVD. By October 2002, this fragile coalition led by Balkenende had fallen apart, mostly because the LPF politicians endlessly bickered among themselves. The January 2003 election was a victory for the PvdA, which won back nearly all the seats they had lost in the May election while the CDA survived as the largest party. At the end of March, officials of the PvdA and CDA parties were still negotiating the finer points of a coalition agreement more than two months after the election.