The County of Dublin and its capital city can trace their roots back to early hunter-gatherer settlements from around 5500 BC. The first farmers began working the land roughly 4000 years BC, and it was at that time the many megalithic tombs and cairns that can be found all over Co. Dublin and the surrounding area were built.
Dublin city's advantageous location around the mouth of the River Liffey was most likely the result of a natural ford, which would have been an important crossing point. Later, its proximity to what was to become Dublin Bay allowed it to evolve into a major port. During the iron age, however, this necessitated the construction of ringforts at key points around what would later become Dublin's suburbs, including Rathfarnham, Rathmines, Rathgar and Raheny, as well as throughout the rest of the county.
Actual data from these early periods is scarce, but a contemporary collection of tales and legends, called The Book of Invasions, states that two legendary Irish kings, Conn of the hundred Battles and Mug Nuada, separated the country between them, all the way to Galway from what is now Dublin High Street. Ancient Greek visitors recorded settlements at the heart of Co. Dublin as being well established as early as 140 AD, while reliable records began around the middle of the fifth century, about the time that King of Dublin Alphin mac Eochaid was converted to Christianity by Saint Patrick.
From 795 through to 902 was the Viking Age in Co. Dublin, and it began with Viking raids throughout the region and along the Liffey, lasting until the ruling Norse family was expelled. In that time many Viking settlements were established along the river, but around the end of the tenth century AD, Norse King Glun Iarainn agreed to pay taxes to High King of Ireland Máel Sechnaill Mór and accept Irish law.
After conquering England, the Normans invaded southern Ireland in 1169 and moved the seat of power from Tara to Dublin, which caused almost all of the region's Viking inhabitants to migrate northwards. The remaining Irish population settled into a tense coexistence, with increasing aggression leading to the building of fortifications around the region, to protect against The Pale, in the fourteenth century. At this time, major Dublin landmarks such as St Patrick's, Christchurch Cathedral, and Saint Audoen's Church were being built.
Further conquest followed in the sixteenth and seventeenth centuries, as the Tudors took control of the entire Ireland and continued the county's struggle under English rule. And, despite the advent of the industrial revolution, the region didn't prosper as well as other parts of the country, with a constantly high amount of unemployed even after the efforts of Guinness, Jameson and Jacob's.
By 1914 though, it finally looked as though Ireland may return to independent rule. However, it took another decade of violence and instability to finally achieve it, but since then Dublin and its surrounding county have developed reputation for culture, friendliness and a warm welcome that is famous around the world.