The holy vision: a united England
Æthelflæd was born into a country ravaged by the Danes, or Vikings. 'Viking' was a verb rather than the name of the people; to go 'viking' was the act of raiding. Many of the Danes were traders, more concerned with settling in rich land that they could farm, than the violent, bloody raids that we think of today, though they did happen. They would sometimes trade their way through the winter, and raid through the summer. Alfred, clinging to a tentative peace deal and facing more raids, decided that the Anglo Saxon kingdoms would need to be united and fortified as one in order to stand against the Danes. He envisioned one England, unified by one religion, and codified by the same laws. Christianity was in its second wave in England, but the relationship with its people was still tumultuous. There had been a brief dalliance with it during the Roman occupation, wherein the richer classes of Britons, in an attempt to identify themselves with the sophisticated, civilised Romans, began to adopt the religion, albeit often in conjunction with their own gods. But soon after the Romans left, the Angles and Saxons arrived, and many Britons returned to their Pagan beliefs. Christian missionaries under Augustine then brought the faith back to them in the 6th century. Wessex became Christian when it's King, Cenwahl, was baptised, and the faith slowly expanded. Though pockets of paganism still persisted, Christianity held on, even through the Viking raids in 871 AD which targeted the holy island of Lindisfarne. The connection between King and God began to develop, and so did the idea of a Christian England. It was Alfred, the Christian King of Wessex, who began to put the idea into motion.
The unified England of course relied upon alliances between the kingdoms. Part of her father's plan to solidify this was to marry Æthelflæd into Mercia, another powerful kingdom, and one with which Alfred already held ties through his own marriage. And so Æthelflæd married Æthelred, Ealdorman of Mercia. By this point, Alfred had begun calling himself King of the Anglo Saxons, something which Æthelred seems to readily accept. While much of England besides Wessex was held by the Danes, Mercia was under threat from new Northmen; the Norwegians, who had settled in Ireland, and were using it as a base whilst they raided the west coast of England. And so, in 879 AD, Æthelred submitted to 'the Royal will.' To cement this alliance, Æthelflæd was given in marriage to him. Alfred helped Æthelred regain control of London in 886, which he then gave back to him, possibly as part of his daughter's dowry. It is believed that Æthelflæd and Æthelred married around this time, when she would have been aged around 16. According to Asser, Alfred's biographer, they married once Æthelflæd was of appropriate age, implying that they were betrothed earlier while she was still a minor.
Lady of Mercia
Newly married, Æthelflæd became co-ruler of Mercia alongside her husband. A few years after their wedding, their only child Ælfwynn, a daughter, was born after a difficult labour in around 888 AD. Æthelflæd proved to be a competent leader, working alongside her husband to keep the Danes out of Mercia, reinforcing the northern borders. A camp of Vikings, forced to leave Ireland after an uprising, were permitted to stay outside Chester, until they grew restless, and attempted to attack the city. Æthelflæd resolved to fight back against the Danes, ostensibly outside the city, but it was a trap. The Mercian army appeared to retreat, and the Danes, in pursuit, were lured into the city walls where the rest of the army awaited them. Chester was a powerful northern base, close to the Mercian border, so in 907 AD Æthelflæd saw to it that the old Roman city walls were reinforced. Her husband appears to have had no part in the Chester attack. There is some evidence to suggest that Æthelred, who suffered from illness, may have been incapacitated from as early as 902, meaning Æthelflæd would be responsible for most of the running of the kingdom. He at last succumbed to his illness in 911 AD, leaving his widow as the sole ruler of Mercia.
Endeared to her people, she soon earned the title 'Lady of the Mercians'. But why lady, and not queen? One theory harks back to her father's reign, and the works of Asser. Her mother Ealhswith was never called queen, but was the first to be dubbed hlæfdige, lady. Asser refers to the story of Eadburh, daughter of Offa and Queen of the West Saxons, who, after marrying the Wessex King Beorhtric, 'began to behave like a tyrant' and '...do all things hateful to God and men.' After her husbands death in 802, she disgraced herself in an affair, and was expelled from the convent to which she had retired. This drove the men of Wessex to refuse to call the king's wife queen, and the tradition apparently stuck. Perhaps being of the House of Wessex, Æthelflæd chose to follow the same tradition, despite ruling Mercia.
After building the fortress at Chester, Æthelflæd expanded her building repertoire, building fortresses throughout Mercia between 912 and 915 AD. Seven of these locations are known to us: Bridgenorth, Stafford, Runcorn, Chirbury, Warwick, Eddisbury, and Tamworth, where a statue of her stands today. After her husband's death, Æthelflæd turned to her brother Eadweard (better known as Edward the Elder), now King of Wessex, who readily offered his support. Like his sister, Eadweard shared his father's ambition for a united England and continued to work toward it, though it would be his son, Æthelstan, who would finally be crowned King of England. The siblings formed a strong partnership, facing the Danes against her allies in Wales and continuing to drive them north. Æthelflæd had gotten York on her side, and was headed there when she died suddenly in 918, in Tamworth. While he allied with his sister, after her death Eadweard replaced his niece as ruler of Mercia, dissolving Mercia into the kingdom of Wessex, a move that seems to have faced little opposition from the Mercians. The young Ælfwynn was exiled, and likely spent rest of her life in a convent. A harsh way to treat your niece, but this was no doubt a step toward the united England they so hoped for. Ælfwynn was likely well educated, tutored at her mother's court alongside her cousin Æthelstan, who's education was praised by William of Malmesbury. However, it appears she lacked the skill and charisma of her mother that made her so popular with the people of Mercia.
Æthelflæd is buried in Gloucester, another city which she helped fortify. She is laid to rest with her husband in St Oswald's Priory, which the pair established.
Sources:
http://www.bbc.co.uk/religion/religions/christianity/history/uk_1.shtml
http://thefreelancehistorywriter.com/2012/07/06/aethelflaed-lady-of-mercia/
The Seven Ages of Britain: the fourth age, 400-1066, Documentary, Bettany Hughes
Æthelflæd: Iron Lady of Mercia, Alex Burghart, BBC History Magazine
http://www.historic-uk.com/HistoryUK/HistoryofEngland/Aethelflaed-Lady-of-the-Mercians/
Asser's Life of King Alfred, translated and with notes by Simon Keynes, Michael Lapidge, (Penguin Classics, 2003)
