of co-regency reduced the chaos quite a lot. The institution of coregency is different from that of vice-regency, where an adult person (in Ancient Egypt often the mother of the king) functions as Legal guardian, ruling in the name of the underage king. Some of the female vice-regents of Egypt rose to a status of equal to the God-Kings, becoming co-rulers as can be seen in the famous case of Hatshepsut. After the death of her husband Thutmose II, Hatshepsut ruled in the name of Thutmose III, her nephew and stepson. Then, latest in year 7 of Thutmose III's reign, she took over royal regalia and was then titled King of Egypt under the Throne name (prenomen) Maatkare. For later periods of Pharaonic Egyptian history, the existence of the institution of coregency has been put into question by Egyptologists, while, "the Ptolemaic and Roman period examples being the most securely identified". Ancient Israel In the book The Mysterious Numbers of the Hebrew Kings, Edwin R. Thiele proposed co-regency as a possible explanation for discrepancies in the dates given in the Hebrew Bible for the reigns of the kings of Israel and Judah. At least one co-regency is explicitly documented in the Bible: the coronation of King Solomon occurred before the death of his father David. Ancient Rome It was common during the Principate for a Roman emperor or Augustus to appoint Caesar as designated heir and junior co-emperor. This was merely a tradition and not a formal office until the Tetrarchy, which attempted to codify this arrangement, but quickly fell apart. Britain King Henry II of England installed his eldest surviving son, also named Henry, as junior king. Henry the Young King was not permitted to exercise royal authority and his title as co-king was effectively a sinecure to denote his status as his father's chosen heir. Young Henry predeceased his father without ever ascending to the throne and is not included in the official list of English monarchs. The monarchy of England experienced joint rule under the terms of the act sanctioning the marriage of Mary I to Philip II of Spain. Philip notionally reigned as king of England (inclusive of Wales) and Ireland by right of his wife from 1554 to 1558. Similarly, following the Glorious Revolution, Mary II and her husband William III held joint sovereignty over the kingdoms of England, Scotland, and Ireland from 1688 to