The House of Orange-Nassau, the current reigning royal line of the Netherlands, dates to medieval times and includes close to two dozen monarchs in all.

The Nassau half of the house is the older one, beginning with the founding of Nassau Castle by Dudo, Count of Laurenburg near the beginning of the 12th Century. The inspiration for the name of the castle and the house was the German area of Nassau, in the Rhineland-Palatinate. Dudo's sons Arnold and Rupert took the title Count of Nassau.

A split came in 1255, when sons of Count Henry II named Otto and Walram went their separate ways. Those in the Walram Line became known as Duke of Nassau and, later, Grand Duke of Luxembourg. The Ottonian Line went in a different direction and, a handful of centuries later, ended up being the double-barreled-named House of Orange-Nassau when the House of Nassau passed to William I of Orange. This was the famous William the Silent, who fought valiantly for Dutch independence against Spain in what became the Eighty Years War.

The title of the head of the House of Orange-Nassau at this time was Stadtholder, and that title brought with it nominal sovereignty over several and, eventually, all provinces of what became the Dutch Republic. Succeeding William I as Stadtholder was his son, Maurice, who succeeded his father in 1585, after the former's assassination. Dominating Maurice's 40-year reign was the war with Spain, which was still raging when Maurice died. His younger half-brother Frederick Henry became Stadtholder in 1625. Frederick Henry was also a highly successful soldier, guiding the Dutch to a successful Siege of 's-Hertogenbosch in 1629. When he died, in 1647, his son succeeded him as William II.

It was during the reign of William II that the long war with Spain finally ended, with the 1648 Peace of Münster. William II died of smallpox two years later. His only son, William, was born one week after his father died, so ensued the First Stadtholderless Period. The Dutch Republic still had the States-General to run things, and the nominal head of that body during this time was Johan De Witt, who functioned at times as a head of state as the republic enjoyed expansion and prosperity, despite fighting two wars with England. A war with France, which began in 1672, coincided with the return of the Stadtholder, in the form of William III, then of age to rule in his own right.

This was the famous William who, in 1688, accepted England's invitation to become King . William maintained his position as Stadtholder until his death, in 1702. He had no children and had named John William Friso, Prince of Orange, as his heir, but the lack of a hereditary successor proved too problematic for four of the republic's provinces (Holland, Overijssel, Utrecht, and Zeeland) and the republic entered the Second Stadtholderless Period. As before, one man assumed some of the actions of a head of state; that was Grand Pensionary Anthonie Neinsius, who guided the republic through the War of the Spanish Succession. Succeeding Neinsius were Isaac Van Hoornbeek and Simon Van Slingelandt, who shepherded the republic through a handful of tenuous postwar years.

Meanwhile, William III's chosen successor, John William Friso, had died, in 1711. His son was born just weeks after his death and so served as Stadtholder of the provinces of Friesland and Groningen but with his mother as regent until 1731. It wasn't until 16 years later, in 1747, with the War of the Austrian Succession nearly finished, that the four recalcitrant provinces gave their consent for William to lead them. He ruled for just four years before his death.

When William IV died, his son, also named William, was 3. The boy became William V and operated under four regents until he came of age, in 1766. He proved an autocratic Stadtholder, angering many in the provinces who had enjoyed more autonomy under previous leaders. The disastrous results of the Fourth Anglo-Dutch War, in 1780, left the Dutch Republic destitute and the government in disarray. A short five years later, William fled the republic in the face of armed opposition. The resulting Batavian Republic ended the rule of the House of Orange-Nassau, for a time.

French Emperor Napoleon Bonaparte declared the Kingdom of Holland in 1806, with his brother Louis on the throne. That experiment lasted four years and then Napoleon, frustrated with his brother's performance, dissolved the kingdom and annexed the territory into the French Empire.

France was again at war with other European powers, during the War of the Sixth Coalition. The Allied powers won a convincing victory at the Battle of Leipzig in October 1813, and one of the results of that battle was France's relinquishing of the Orange-Nassau territories. William V's son, also named William, was around and ready, having lost his lands and titles to the French with the ascent of Louis Bonaparte. William VI became, in 1813, the Sovereign Prince of the United Netherlands and then, two years later, William I, King of the Netherlands. This was the birth of the modern country.

William I was the monarch at the time of the Belgian Revolution. He was dismayed at the uprisings against his rule, and he authorized continuation of the war for reunification for several years. The 1839 Treaty of London ended the war and made the split official. That treaty also changed the governmental makeup of the Netherlands, so much that William decided to abdicate rather than rule over the newly constituted country. He stepped down in 1840, leaving the throne to his son, who became King William II.

Eight years into the new king's reign, after the Revolutions of 1848, the country had a yet another new constitution, which created a parliamentary democracy. He died suddenly the following year. His son William succeeded him, as William III.

William I had also been Grand Duke of Luxembourg. His son and then his son also had that title, serving as head of state of the tiny entity. In 1856, William III, who wanted to rule more as a monarch of old and not one constrained by a parliamentary democracy, instituted a new constitution in Luxembourg that gave him more authority. His advisors and legislative leaders thwarted similar attempts in his native Netherlands. He continued on the throne until his death, in 1890. Succeeding him as monarch was his daughter, Wilhelmina. She was all of 10 at the time and so ruled initially under the regency of her mother, Emma.

Wilhelmina became queen in her own right in 1898. She was on the throne for 50 years, presiding over great change in her country and in the wider world. She spoke out against British conduct in South Africa, which led to the Boer Wars. She insisted on her realm's being neutral in World War I, and her neighbors respected that with, even though Germany invaded and occupied Belgium in 1914.

German forces invaded and conquered the Netherlands in 1940, and Wilhelmina went to the United Kingdom, there to function as head of a government in exile. After the end of World War II, she returned, ruling again in country until 1948, when exhaustion forced to abdicate in favor of her daughter, Juliana.

The second female monarch's reign included independence for the Dutch East Indies, which became Indonesia, and later, Suriname. Queen Juliana also gained widespread support by joining rescue and recovery efforts after a powerfully destructive storm in 1953. She abdicated on her 71st birthday, in 1980. Her successor was her daughter, Beatrix.

The new queen was on the throne for 33 years. Highlights of her reign included the creation of the European Union, with the Treaty of Maastricht in 1992. She presided over other geographical and economic changes, such as the dissolution of the Netherlands Antilles, in 2010. Beatrix abdicated in 2013. Succeeding her was her son, Willem-Alexander, the current monarch.