"Je Maintiendrai," "I will maintain," is the motto of the House of Orange and Nassau, the Royal Family of the Netherlands.
The phrase is supposed to have been uttered by William the Silent, Prince of Orange and Nassau, who was elected William I, Stadholder of the Netherlands (actually, of Holland and several other provinces), in 1572. This was in the midst of the great revolt of the Netherlands against Spain. Considering that Spain was the greatest power of the day and had (it seemed) unlimited wealth from the New World, the revolt was a desperate business and not long before this had seemed altogether a lost cause. However, the Dutch were stronger than they might seem now, since they were rapidly becoming the first great modern commercial and banking power, while Philip II of Spain was simply spending his Mexican and Peruvian money on unprofitable imperial and religious projects. Thus, even during the revolt, Dutch ships were carrying much of Europe's trade, and the Spanish money from the New World tended to end up in Dutch hands. After the bankruptcy of Spain and the mutiny of Spanish Army in 1576, and the failure of the Spanish Armada against England in 1588, Dutch independence was effectively secured, though not officially recognized until 1648. William himself was assassinated in 1584.
One hundred years after William's election, when Louis XIV of France invaded the Netherlands in an act of naked aggression, the Dutch elected as Stadholder William the Silent's great-grandson: 
William III (1672-1702). The Netherlands was again in desperate circumstances. The King of England at the time, Charles II (1660-1685), was a secret Catholic in secret league with Louis XIV. Also, since England was a commercial competitor to the Dutch, England's interests in the long run seemed better served by a strategy that would enable her to move with force against Dutch trade. Nevertheless, the Dutch and William, a solid if not a great general, held off both England and France, in part by opening the dikes against the French army, as his ancestor had opened the dikes against the Spanish. (Centuries later, Queen Wilhelmina is reported to have bluntly warned Kaiser Wilhelm II that she would do the same should the Germans try to invade her county; but, sadly, flooding the land became neither a timely nor an effective strategy against German paratroopers in 1940.)
Soon circumstances changed extraordinarily. The English were restive against Charles's brother James II (1685-1688) when it was clear he wished his young Catholic son to supersede his Protestant older daughters, Mary and Anne, in the succession. William landed with a Dutch army in England in 1688 and easily drove James out of the country. This was the "Glorious Revolution"; and, as it happened, William was married to Mary. William was also a grandson of King Charles I (1625-1649) through his mother (also named Mary), so he and his wife Mary were considered to have equal claim to the throne, resulting in the only dual monarchy in English history: the Mint resorted to the style of the Ptolemaic brother-sister rulers of Egypt to represent both William and Mary on the coins.
William and Mary were offered the throne of England, Scotland, and Ireland in 1689 with the provision that they accept Parliamentary supremacy and assent to a Bill of Rights. They did, becoming King William III (1689-1702) and Queen Mary II (1689-1694), enabling the country to take another step towards parliamentary democracy and the establishment of individual rights. This kind of thing, of course, did not yet apply to Ireland, where Catholics were all but without civil rights. Consequently, William had to deal with the Irish rallying to King James. William's victory at the Battle of the Boyne on July 1, 1690 (July 11 on the Gregorian calendar), finished off James as King and also secured the position of the Scotch-Irish Protestants of Northern Ireland. The battle has been remembered yearly by the Protestants ever since, much to the chagrin and fury of Irish Catholics. It's anniversary is celebrated, however, on July 12, which is actually the date on the Julian Calendar of the Battle of Aughrim in 1691.
The Protestants also adopted for themselves William's heraldic color of Orange, which has continued to symbolize Irish Protestants, even in the Irish Republic (where one stripe of the Irish flag is orange), and was carried by Scotch-Irish immigrants to America, resulting in more than one Orange County in the United States. Although initially more successful in America than Irish Catholics, and often in violent confrontations with them, the Scotch-Irish tended to settle in mountainous frontier areas -- along the Appalachians from Virginia down to Tennessee and North Carolina and in other places like the Ozarks -- where they distinguished themselves as Indian fighters and as anti-slavery Unionists during the Civil War but then came to be bypassed by economic development, resulting in the status of one of the poorest ethnic groups, to the extent that they can now be distinguished from other groups, in America today.
With Great Britain and Ireland in hand, William's resources were vastly expanded to pursue the great War of the League of Augsburg (1688-1697) against Louis XIV. This ended the course of French aggression, though the job soon had to be done all over again in the War of the Spanish Succession (1701-1714). The salvation of the Netherlands, however, was also the end of its 17th Century greatness. With a potentially vastly larger economy and resources, England economically surpassed the Dutch more easily as an ally under William than she had as an enemy under Charles II. William was too busy using all his resources against Louis XIV to play favorites with his Dutch homeland against England. Despite its long position in the economic vanguard of Europe, the Netherlands soon sank from the ranks of Great Powers.
Therefore, I adopt "Je Maintiendrai" as the motto for my Vita:
Stadholders and Kings of the Netherlands