The Princess Helena (Helena Augusta Victoria; 25 May 1846 - 9 June 1923) was a member of the British Royal Family, the fifth-born child and the third daughter of Queen Victoria. She later married into the Ducal House of Augustenborg and was styled Princess Christian of Schleswig-Holstein.

Princess Helena was born on 25 May 1846, at Buckingham Palace, London. Her mother was the reigning British monarch, Queen Victoria, a grandchild of King George III through his fourth son, Prince Edward Augustus, Duke of Kent. Her father was Prince Albert of Saxe-Coburg-Gotha. As a daughter of the sovereign, Princess Helena was styled Her Royal Highness from birth. She was known in the family as Lenchen. She was christened in the Private Chapel at Buckingham Palace by William Howley, Archbishop of Canterbury on 25 May 1846. Her godparents were Hereditary Grand Duke Friedrich Wilhelm of Mecklenburg-Strelitz, The Duchess of Orléans, and The Duchess of Cambridge.

In September 1865, while visiting Coburg, she was introduced to Prince Christian of Schleswig-Holstein (22 January 1831 - 28 October 1917), the third son of Christian, Duke of Augustenborg and Countess Louise of Danneskjold-Samsoe, an ethnically Danish prince. They were both great, great grandchildren of Frederick Prince of Wales (father of George III of the United Kingdom), which made them third cousins. Prince Christian was also in the line of succession to the British throne, but far down the list.

The couple became engaged in December of that year. Queen Victoria gave her permission for the marriage with the proviso that the couple live in England. They married at the Private Chapel at Windsor Castle on 5 July 1866. Seven days before the wedding, the Queen granted her future son-in-law the qualification of Royal Highness. This style was in effect in Great Britain, not Germany, where Prince Christian, as a son of the Duke of Schleswig-Holstein, was only entited to the style Serene Highness.¹

Helena was now known as Her Royal Highness Princess Christian of Schleswig-Holstein. Helena and Christian lived at Frogmore House in the grounds of Windsor Castle and later at Cumberland Lodge in Windsor Great Park. Together they had six children:

The couple's first son, Prince Christian Victor, died of enteric fever at Pretoria, South Africa, while serving with the British Army during the Second Boer War. Prince Albert, the second son, later moved to Germany where he succeeded his childless first cousin, Ernst Günther, as Duke of Schleswig-Holstein-Sonderburg-Augustenburg in 1921. Princess Marie Louise was married in 1891 to His Highness Prince Aribert of Anhalt (18 June 1844-24 December1933), the fourth son of the Duke of Anhalt. This marriage ended in divorce in 1900. Princess Marie Louise returned to Britain, where with her unmarried sister, Princess Helena Victoria, she carried out public and official duties as member of the British Royal Family for forty years.

Queen Victoria granted the children of Prince and Princess Christian the style of Highness in May 1867.

Helena, along with her younger sister, Princess Beatrice, remained close to her mother, especially after the death of Prince Albert. She was the patron of the Young Women's Christian Association (YWCA) and the National Society of the Prevention of Cruelty to Animals and Children. She worked to improve the country's nursing facilities and founded the Princess Christian Nursing Home at Windsor.

During World War I, rising anti-German sentiment forced the British Royal Family to sever its links to Germany and to discontinue the use of various German titles and styles. In July 1917, Princess Christian's nephew King George V changed the name of the British Royal House to the House of Windsor and discontinued for himself and all other descendants of Queen Victoria who were British subjects all "other German Degrees, Styles, Dignities, Titles, Honours and Appellations." Prince and Princess Christian and their two daughters dropped the territorial designation "of Schleswig-Holstein-Sonderberg-Augustenberg" and instead became known as Their Royal Highnesses Prince and Princess Christian, Her Highness Princess Marie Louise, and Her Highness Princess Helena Victoria, respectively.²

Princess Helena lived to see her son Albert become in 1921 the head of the House of Oldenburg and the titular Duke of Schleswig-Holstein.

Helena died on 9 June 1923 at Schomberg House, her London residence, at the age of 77. She was buried next to her husband at the Frogmore Royal Burial Ground in Windsor Great Park.

* 25 May 1846-5 July 1866: Her Royal Highness The Princess Helena * 5 July 1866-17 July 1917: Her Royal Highness Princess Christian of Schleswig-Holstein * 17 July 1917-9 June 1923: Her Royal Highness Princess Christian