Sokemen first appear in writing in the Domesday Book, i.e. roughly two hundred years after Viking settlement in Northern and Eastern England. In Domesday, their land is recorded independently of manors, and in that sense they are separate from other peasants, and only appear in the Danelaw. Although this invites an interpretation of sokemen as a unique class exclusive to the Danelaw, with such a chronological difference from their recording to their supposed origin there are several aspects pointing otherwise.

Before delving deeper into this, it's worth considering what 'soke' meant. Soke seems to have held two definitions in pre-conquest England, one judicial and the other territorial. In the former, for a king to grant "sake and soke" to a noble, he was essentially giving up the profits of justice to the recipient. In other words, the fines and other fees attributed to the judicial process would go to the owner of the soke-right, not the king. In the latter sense, soke could be taken as a territorial grant. These grants are usually interpreted in the form of exemptions or immunities: the land under soke-right would not owe certain dues to the king. In both these senses, theoretically anyone living on sokeland was a sokeman, simply by nature of where they lived.

If anyone on Sokeland could be a sokeman, what was it that truly set sokemen apart? Taking a step back, the term "sokeman" is rare before Domesday. More common are the terms villanus in England at large, and specifically within the Danelaw the fairly synonymous geneat. In Domesday, to be a villanus (or villein) is to be a generally unfree dependent. However, in pre-conquest terms, villani seem to have been no more than what their name implies - villagers. The villanus of pre-conquest England and the sokeman of post-conquest England seem roughly equal. It is possible that the Domesday scribes were simply misinterpreting existing land rights and status. This is reflected in Cambridgeshire and Bedfordshire, where the number of sokemen dropped from 900 and 700 in 1066 respectively, to 177 and 90. These sokemen didn't disappear, though, and with that precipitous drop an according rise in villani occurred. On the one hand, these sokemen may have had their land revoked and been reduced to less free status. Equally, though, the Domesday scribes were just trying to make sense of the complex terminology of status in Anglo-Saxon England.

These pre-conquest villani and post-conquest sokemen were marked by their relative freedom. They were exempt from the more intense labour rents of lower classes, but still owed rent to a landlord. The idea of their "freedom" exists not so much because they were free from the dues of other peasants, but because they weren't slaves. Freemen was a broad class for Anglo-Saxons, and encompassed a wide range of people, sometimes owing significant amounts of goods and services. In the Rectitudines Singularum Personum, a cottager (the terminology deepens) is described as paying "his hearth-penny on Holy Thursday just as befits each free man," apparently establishing him as a free man. Despit this, the cottager "must labour for his lord each Monday throughout the year, or for three days each week throughout the harvest... [he must] guard his lord’s land if one asks him [to], [and] guard the coast, and [work] at [maintaining] the king’s animal-hedge, and at such things such as should [befit] his rank, and he should pay his church tribute at Martin’s Mass." Clearly, free men were not free of every charge and duty.

The villanus, or in the Rectitudines the geneat, is differentiated from other free men in one real form only: he does not have landed labour dues. The geneat still owes dues, varying from providing horses for plough-teams to errand-running to simple payment, but is not required to plough the lord's land himself. This is in accordance with a prominent theory of Anglo-Saxon landholding: the differentiation between inland and warland. In essence, the landlord exerted direct influence over inland, but only collected dues from warland (be they food renders, coin, or labour like the aforementioned errand-running). In this sense, the villanus is best defined as someone inhabiting warland. They were absolutely still dependant to a landlord, but less so than an inhabitant of inland. Important here, in the above quotation from the Rectitudines the cottager is described as working the inland (since he must "labour for his lord," here meaning working the lord's land), but is nonetheless still free.

The idea of a sokeman, then, seems to be more ubiquitous in Anglo-Saxon England than Domesday would imply. Warland was a constant of Anglo-Saxon land ownership, and the inhabitants of warland seem to fill the same social rung as Domesday sokemen. Just as ubiquitous were lower classes, but "serf" here isn't really an apt term.

On the bottom end of the social spectrum, there really isn't such thing as a serf in pre and immediately post-conquest land rights. That idea develops over time, as Anglo-Norman lords intensify demesne agriculture (essentially turning estates of mixed inland and warland into estates of inland), over the later eleventh century and onwards. Instead there are slaves, and peasants that, while technically free, owe fairly heavy dues to their lords. The villanus can certainly be categorised as socially and economically above these people. Outside of the Rectitudines, though, descriptions and concrete evidence of these various classes are scanty. The idea of a lowest class of freeman, perhaps somewhat similar to later serfs, is hinted at in the treaty between Alfred and Guthrum of the late ninth century. Therein, Danish "freedmen" are equated to English "ceorl[s] who sit on gafolland." Gafolland is typically translated to rented land, where the inhabitant would owe Gafolgelda (rent-due) for the land. What the gafolland seems to be describing, then, is inland. Peasants working inland were given small holdings of their own, according to the Rectitudines, geburs (the term used in the Rectitudines) are owed "two oxen and one cow and six sheep and seven acres" in return for their service, that the lord retakes after the gebur's death. In other words, they are basically renting the land. The comparison in Alfred's treaty is "freedmen," emphasis here on the 'd.' These men were at some point unfree - read slaves - and were since freed, putting them at the absolute bottom of free society, just a notch above slavery. If geburs were really comparable to these freedmen, then they are a far cry from villani, who in that same treaty fall under the term Englishmen broadly. The freedman and ceorl on gafolland are each given a wergild of 200 shillings, whereas the Englishman a wergild of 8 half-marks. The difference here is between what is essentially chump change and the highest wergilds of contemporary English law.

The takeaway, then, is that sokemen were not at all like serfs, or at least the nearest comparable statuses of each were not. Villani, and ceorls on gafolland, fell on opposite extremes of non-noble freemen. Whether or not being a villani was "good" I can't really say. Better perhaps, but dues and obligations still existed. Important here is that both of these statuses were still free. The hearth-penny that the cottager of the Rectitudines pays "as befits every free man" is also expected of the gebur. The society of pre and post-conquest England was in a large part rooted in obligations, and sokemen fit into that equation like any other slice of contemporary society.

EDIT: forgot sources

For the Rectitudines, an online version can be found here: http://www.earlyenglishlaws.ac.uk/laws/texts/rect/view/#edition,1_0_c_10/translation,1_0_c_4_2

My translation of the treaty of Alfred and Guthrum is number 34 in English Historical Documents Volume I, c. 500-1042, ed. Dorothy Whitelock

Also: Rosamond Faith, The English Peasantry and the Growth of Lordship - the seminal text on the idea of warland and inland

Robin Fleming, Kings and Lords in Conquest England

Emma Day, Sokemen and Freemen in Late Anglo-Saxon East Anglia in Comparative Context