Tomorrow King Willem-Alexander and Queen Maxima will kick off a two-day state visit to the UK, during which they will meet with the Queen, the Prince of Wales and the Duchess of Cornwall, and the Earl and Countess of Wessex. On Tuesday evening the two will also attend a state banquet held in their honor at Buckingham Palace, which will serve as home base while they are in London.

The Netherlands and iterations of the Dutch Royal Family have an important relationship with the British Royal Family, not least of whom is a shared ruler – William III. William, once Prince William of Orange, became king alongside his wife, Mary Stuart, after the Glorious Revolution ousted her father, the Catholic James II.

A generation before and William’s mother was in fact another Mary Stuart, daughter of Charles I and sister of Charles II and James II. As such, William and Mary were in fact first cousins. Hey, it was the 17th century. While the first Mary Stuart served as Princess of Orange, her court in The Hague served as a refuge for the exiled Stuarts during Oliver Cromwell’s “reign” in England.

While Willem-Alexander and Maxima are in London they will visit Westminster Abbey and see the vault where William and Mary are buried.

A few decades later and George II’s eldest daughter, Anne, the Princess Royal, also married a William of Orange – and gave birth to another. This William, William V, served as Stadtholder of the United Provinces until 1795, while his son became King William I of the Netherlands in 1815 during the Napoleonic Wars.

Willem-Alexander has sat on the throne for five years, but before him came three consecutive queen regnants – unprecedented in Europe. His mother, Queen Beatrix, served as queen for 33 years before choosing to abdicate, a scenario much more common in European monarchies outside the UK. She herself succeeded her mother, Queen Juliana, who reigned for 32 years between 1948 and 1980. And she inherited from her mother, Queen Wilhelmina, who had reigned since 1890 before abdicating from exhaustion and poor health after pulling through World War II.

Willem-Alexander was born in 1967 in Utrecht, spending most of his childhood in Baarn with his parents and two younger brothers. In 1981, after his mother’s accession, they moved to The Hague, though two years later he started at the United World College of the Atlantic in Wales. He went on to study at Leiden University later in the decade after a stint of military training. Throughout the 90s and aughts, he served in the military, but was honorably discharged before ascending the throne due to the relationship between the government and armed forces.

As for his royal duties, he has sat on the Council of State of the Netherlands, headed by the sovereign, since 1985. Two focus areas of his work are water management, sports, economic issues and supporting the military and veterans.

In February 2002 he married Máxima Zorreguieta Cerruti in Amsterdam, a then-30-year-old Argentinian woman he met in Spain during the Seville Spring Fair in 1999. The two became engaged in 2001 after a courtship that started with Maxima not knowing her suitor was the Dutch heir to the throne, and in fact not believing him when he finally told her. She retained her Catholicism after her marriage, though their children are raised Protestant.

The couple now has three daughters: Catharina-Amalia (b. 2003), Alexia (b. 2005) and Ariane (b. 2007). Catharina-Amalia is expected to eventually succeed, and as such holds the title Princess of Orange. She will assume her position on the Council of the State of the Netherlands upon turning 18, in about three years.

As queen, Maximia’s work focuses on Dutch immigration, particularly initiatives that ease immersion, including language – an immigrant to the Netherlands herself, she is particularly well-positioned to address those issues. She is also a staunch advocate for LGBT rights, micro-financing and the importance of musical and fiscal responsibility training for children.

Early reports of the issue flag that the King’s remarks before Parliament may cause a bit of a stir given that he has been an outspoken critic of Brexit. It’s unlikely this issue will come up during his meetings with members of the BRF, but politically it may be a bit dicier. The Mirror reported:

“[H]e may be in for an awkward meet with Theresa May or other members of Parliament after his remarks during a briefing in the Putti room of Noordeinde Palace, his official residence.

“Although protocol prohibits reporters from taking verbatim quotes, the king made his feelings clear, saying he regretted Britain’s decision to leave the bloc, and wishing the 2016 referendum result had gone the other way.

“He is also due to bring up the topic of Brexit when he meets Dutch citizens living in the UK, according to the Dutch Royal Family.”

In any event, expect white tie and tiars tomorrow evening for guests attending the state banquet at BP. Photos can be a bit iffy on these occasions, but there will likely be a formal photo-call for Queen Elizabeth, King Willem-Alexander and Queen Maxima, while we usually get arrival shots for other members of the family. Hopefully the Duke and Duchess of Cambridge make an appearance, but I’ve heard nothing definitive one way or the other.