The first time I encountered Harn was in a rack around 1984 at Games Unlimited in Pittsburgh. It came in a folder (shown to the left) with two books and a map. The Harnview and the Harndex.
Harnview was an introduction and overview of Harn. The first section was the Overview containing the Introduction, Culture Map, Cultures, Religions, Economic Map, Economics, History, Chronology. It is well written and packed a lot of information in only 20 8.5 by 11 pages.
The remaining 12 pages was titled Using Harn and consisted of a brief explanation of the regional map, a systemless method of character generation, an explanation of the pregame, time and motion, scenario suggestions, Encounter Tables, the infamous weather generation table, and the movement table.
The pregame was eye opening in 1983. It basically outline a simple procedure where you use the character generation chapter to come up with a background. Then in a one on one session with the player you bring the character up to the "present" in the campaign. The section is brief only taking up one column on one page. However it proved the key in keeping the Majestic Wilderlands approachable for all the players that I referee afterwards.
The Using Harn section has a lot of good information for use in other games. The weather table is one of the most straight forward I seen. It involves using a track with 20 elements. You have another table that you roll on that tell whether you move up 1, no change, down 1, or down 2. The track is structered so that weather changes happen naturally. It one of the more elegant solutions I seen.
The only problem is that is only for the cool temperate climate that dominates Harn. The Ivinia Regional Module as an additional sub polar chart but that where it stopped. In practice I use it only when weather makes a difference such as crossing mountains or venturing into the wilderness.
The encounter tables I used quite a bit. They reflect well the gritty medieval feel of the majestic wilderlands. Monsters are a part of the table and for that I go into Chgowiz's Swords & Wizardry Reference guide to roll up instead of the Harn sub table.
As for Harn itself it is a wooded isle the size of Madagascar and the climate of the British Isles. It's long axis runs east to west. Harn is part of the continent of Lythia which is on the world of Kethira.
The map is huge and one of the best map I ever seen for a roleplaying setting. It was ingenious at the time for it's depiction of both terrain and vegetation intermixed. Vegetation was represented by color. Terrain was represented by semi-transparent fills. This allow forests, heath, and plains to cross hills and mountains naturally.
Harn was the original arrival point of Kethira's Elves and possibly the Dwarves. For a long time it was a sylvan island until migrating barbarians made landfall. First the Jarin who made peace with the Elves and Dwarves and then later the Lythians who made war.
The wars with the Lythians ended the Elves rule of Harn and in the wake of their downfall scattered tribes and petty kingdoms made Harn their home. A dark lord by the name of Lothirm arose a couple of centuries later and threatened to conquer all of Harn. To cement his power he created (or imported) the Gargun (Orcs). He met his downfall in a war with the dwarves. After this dark period of history several kingdoms were created from the wreckage of the surviving petty kingdoms.
Melderyn, Home of wizards and perhaps the strongest Harnic Kingdom.
Kaldor, the largest Harnic Kingdom
Chybisa, the last of the old petty kingdoms now much shrunken due the surrounding barbarians.
In the west the geography is dominated by the Thard River and the Corani Empire was formed along it. It grew to be Harn's largest state and then collapsed in a series of civil wars. It was replaced by the Theocracy of Tekhos dedicated to the worship of the undead god Morgath. Eventually the Theocracy broke up. The northwest was conquered by barbarians who founded the Kingdom of Rethem. Rethem still allows the worship of Morgath and other evil gods. The northeast became the Thardic Republic and dreams of the restoration of the Corani Imperium. The south became the Kingdom of Kanday dedicated to the worship of Larani. Larani is a goddess of justice opposed to the evil deities of Rethem. All three vie for dominance in western Harn.
To the northern the last stronghold of the Jarins was conquered by Ivinian Vikings who founded the Kingdom of Orbaal. Azadmere is the last surviving kingdom of dwarves on Harn. And the Elves retreated to Evael in the south central portion of Harn.
All of these lands are surrounded by a dozen barbarian tribes each with their own cultures.
The details of all this are given in the Harndex which is an alphabetical listing of places, people and events of Harn. It is 64 pages, not long but densely packed with information. The most useful bits of the harn is the medieval information which includes an extensive pricelist.
While I only ran Harn as a campaign a handful of times the books have proven to be a gold mine of information that entered into my Majestic Wilderlands. Today they set next to my desk as they are used constantly for reference and inspiration.