The fall of the Roman Empire severed the political links between many of the European states. In Venice and Sicily, trades in luxury goods with the East continued to some extent, but on the rest of the continent towns were too few and too small for a consumer market to take off as it did in the Ayyubid and Seljuk territories to the south, or the Byzantine Empire. Even when the Holy Roman Empire came to most of Europe (excepting the Scandinavian countries who mostly traded with each other, Sicily, which acted as the frontier post of the Byzantine Empire, and the Saxon territories to the north and in the British islands), each country had to be self-sufficient.
Except in England, the old Roman concept that land belonged to the State was cast down with the advent of Christianity and the concept of the monarch appointed by God through his agents the saints. All land belonged to the highest ruler, whether that be the King or Queen, or the Emperor. That ruler would keep some of the land for themselves, usually choice hunting grounds, strategic ports or other areas of national importance, and the rest would be divided into holdings for tenants, who would have to pay the ruler with goods and with labour to cultivate or keep the ruler's own land. The monarch's barons, who held land directly from the monarch, would usually consider it beneath themselves to work their own land, and in their turn leased it out to tenant farmers or local lords with tenant farmers beneath them, again, keeping the best of the land for themselves. At the bottom of the scales, lands would be shares in large fields surrounding a village, and the community affairs would be supervised by the local bailiff.
Though people lived in villages, the main social unit is the estate: a self-sustaining social unit. Most estates provide food and goods for their own consumption, with some of the richer estates managing to provide excess for sale. Tenants would owe an amount of food or goods to their lord before they were permitted to keep any for themselves; this is why in harder times villagers look to their lord's well-stocked barns to keep them from starving. How large the portion taken is and the extent to which lords can be relied upon to provide in times of need varies wildly; prior to the laws of Henry II of England all affairs on the estate were governed by local laws and enforced by the bailiff, usually in the pay of the landowner.
In return for goods and labour, lords were expected to provide protection for their tenants, usually through hiring mercenaries or having loyal vassals to fight for them. Vassals were free-born members of war bands of a monarch or baron, bound by a personal oath of loyalty of service in exchange for protection, which bound only themselves but not their children. Vassals who demonstrated exemplary loyalty or notable success could expect to be rewarded with an estate of their own, to enjoy for their lifetime, from which they could pay for vassals of their own. Tenants, on the other hand, were not free - they swore to stay loyal, to live and work on the estate and not move to other estates, and for their children to do the same, in return for their protection. If a tenant married a tenant from another estate, whichever tenant moves and changes their allegiance is expected to pay merchet, a sum of money to compensate the lord for their children becoming tenants of someone else. The obligation to pay merchet differentiates free people from the unfree.
There are many stories of this system being abused. Lords can refuse to protect their tenants, or demand high amounts of goods and/or services in return for land, impoverishing their tenants and keeping them 'loyal' through desperation. Lords whose vassals terrorise the estates, safe in their close relationship with the lord. Bailiffs dispense the justice they are paid or terrorised to; a bailiff who rules against their lord may return home to see their family dead, their house burned or their job given to another. Tenants of absentee lords frequently put in minimal work on the lord's estate, leaving communal barns empty and land wasted; in times of famine whole villages suffer as a result. Tenants could marry outside the estate but act as spies for their lord, particularly in times when the old and the new lords are at war: destroying crops, sabotaging weapons and carrying back information: dangerous work, but highly rewarded by the right lord.
From this system feudalism emerged: a system which granted security to both lords and their vassals (admittedly not to tenants, but not since Arthur had a ruler cared about the unfree). Feudalism was relatively simple: a person would hand over their service and lands, swear loyalty to a higher ruler, and become their vassal. The lands would then be given back to them by the ruler as a benefice, and while technically the lord would have the right to grant away to another the land belonging to the vassals, a lord who did this would not keep his power for long. This is a society bound together by the individual oaths of individual men to individual lords: the most essential obligation of the vassal is their service in wartime and the mst essential obligation of the lord is to provide protection. Lords have no legal right to refuse to accept a vassal if they offer homage; however, the more unscrupulous will simply arrange to have unwanted vassals disposed of. The coming of the Fae has led a new degree of intensity to vassalage: oaths previously sworn on Bibles or to saints are now largely enforced by Fae spells. On the continent, the number of Fae seeking homes and willing to offer service in return for protection led to increased competition for vassalage; this was significantly less of an issue in England as few Fae made their home here, and those who did rarely wanted to serve any human. There are rumours that the sorceress Morgana had Fae vassals; any records of such would be in her library in Tingatel castle.
Three languages are widely spoken in England: English, by almost everyone, French, by the nobility and those learned in culture, and Latin, by restricted and prestigious Churchmen, and those with a background in law or education. There are other languages - Cornish people speak Cornish, the Welsh and those who live on the Welsh Marches speak Welsh, and Jewish people speak Hebrew. However, in day to day life, most people find English to be the most common tongue spoken.
Latin is the language of the international educational communities, such as the University of Paris. It is also the language of other international communities, such as trade and shipping. Many captains and merchants do not speak Latin themselves, but would seek to take with them someone educated by the Church.
Latin is the language used for writing important or legal documents. Charters of land ownership, writs of law, texts of church service books, works of theology and science and the life stories of saints are all written in Latin. Those needing a translation would go to their local priest for guidance.
French is the language of the cultural elite: it is the language of the Norman conquerors and is considered a superior language to English. Sermons at court and in cultured circles are preached in French, largely because after the Conquest the majority of clerics appointed to English bishoprics were French. Those of low social standing are discouraged from learning or speaking French - they may learn Latin as they need and can, but French is reserved for persons of note.
The French consider that there are two types of their language: French, as spoken by French people in France, and a different, inferior, more uncouth sort of French spoken by Normans living in England.
A few points: