In Homeline's history a Czech probably invented our modern type of
Moldboard plow around the fifth century CE and it slowly diffused through Europe. There were earlier types. On
Albion-7(Albion being used for major changes in the history of pre-Saxon Briton being the main divergence point) someone introduced the Moldboard Plow into Britain in later Roman times. Just as the new Plow was introduced into Normandy the Roman state collapsed to the point that all further investment in new agricultural technology slowed to a snail's pace.
Still, a far more populous Celtic Britain repulsed the Saxon raiders and absorbed Saxon immigrants. The Britons formed a council to rule them which evolved toward an oligarchical republic. Viking Settlers later brought the idea of the
Thing. It was soon seen as easier to use this idea of government to co-opt the Vikings than to war against them.
The local year is 935CE. Britainnia is a powerful Kingdom that Controls the British Isles, Normandy, and Brittany. They're improving their ships seeking better connections with the Spanish Caliphate, the Mediterranean, the Canaries, and points South.
Basically, it's a print the legend medieval adventure setting. Skim over old
Prince Valiant stories for ideas to steal. Also look at pulp historical fantasy and adventure tales for further inspiration.
The tech level is an advanced TL3 (More like the late 14th century than the early tenth) but some sailing and navigation technologies are at TL4 (basically those that make the story better.)
Most of this world is low Manna but areas of Normal and High Manna exist. These are normally achieved through the use of sacred architecture but areas of natural variation also exist.
Knowledge of Magic is rare as is Magery. Assume that Magery requires an
Unusual Background cost.
This is a Q4 world which has the problem of attracting large numbers of Swagmen. The ICops want to know why so many Swagmen seem drawn to this one world.