Gruumsh

Patron god of the Orc race, Gruumsh was a one-eyed humanoid with a penchant for destruction.

History

The orcs were a humanoid race from another set of realms that were, throughout history, transported to Toril in great invading waves. Orcs were militaristic, expansionistic, and stratiocratic (ruled by the strongest).
When the orcs came to Toril, they brought with them a pantheon of gods geared for war. The leader of the Orcish pantheon was Gruumsh, god of strength, battle, and endurance. On his arrival in Toril, his orcish horde met a great host of elven warriors, and Gruumsh met Corellon in battle. The fight was not one-sided, but Gruumsh lost his left eye to Corellon's arrows, and his horde, while not driven back, was stopped cold.
The orcs left in Toril settled to a nomadic tribal existance in wastelands and out-of-the-way places, while occasionally forming vast hordes and attacking the forested elven kingdoms, the grassland realms of the humans and the mountainous strongholds of the dwarves.
Over millenia, the nature of the orcs changed. No-longer driven by whatever forced them to cross worlds, the orcs settled into the fierce tribal race eventually known as Grey Orcs.
When other gates were opened, introducing a fresh wave of invading (Green) orcs into the world, Gruumsh once again became the bloodthirsty warrior of his follower's belief, but Gruumsh now considered strength differently, and after the initial incursion, a dogmatic rift now began to be felt between the Green and the Grey. Unfortunately, a one-eyed god of destruction calling himself Gruumsh continued to lead the orcs in mutually destructive battles against the races of humankin.

Many Arrows

It was not until the rise of Obould of the Broken Arrow tribe, who began to conquer large swathes of the northern kingdoms, including the dwarvish Citadel Felbarr, (later known as Citadel of Many Arrows,) that things changed. After a fight against heroes including Drizzt Do'Urden, he declared a ceasefire and signed a peace establishing the Kingdom of Many Arrows, a recognised Orcish land.
It was with the Many Arrows that a new version of Gruumsh was established, one which recognised various kinds of strengths and worked alongside other species to make use of them. Initially having diplomacy with goblinoids, worgs and ogres, the new Gruumsh's willingness to work with, (or subjugate,) other species grew in reputation until a new kind of monster-diplomacy, where strength, or ability to enhance the strengths of others, became political power between orc, goblinoid and giant, (and monster,) and eventually humankin races as well.

Portfolio

While the two versions of Gruumsh both promoted many of the more destructive aspects of his portfolio, such as the primacy of strength, the Orc's natural endurance and berserker tendency, and the rivalry with humans, dwarves and particularly elves, the new version of Gruumsh also promoted the different aspects of strength, both physical and skillful, as well as the mental and social strengths, like leadership, strategy and supporting allies.
He also recognised the difference in personal strength and the strength of a tribe or kingdom, although if a leader expected the latter, he should be sure of the former. If an Orc recognised that a kingdom was strong while the leadership were personally weak. For instance "The soldiers of Waterdeep stood ready to repel our mighty horde, while their masked lords acted a bunch of flacid, gold-seeking, catamites." It was a double insult to both to the lords and to those willing to fight in their name.
The most striking difference was in this new Gruumsh's influence over inter-species diplomacy, where, using Gruumsh as intermediary, cunning kobolds might make use of ogre strength, while duergar masons under the flag of Gruumsh, could offer their building services to manticores seeking lair upgrades.
Speculation
Speculation
Talos is thought to have taken advantage of the similarity between his avatar and Gruumsh's and used his position as the god of destruction to turn the willing orc hordes into his tools without even using his own name. How he would have supplanted Gruumsh's connection with his own Orc subjects is unknown. Possibly by Talos merely being the more powerful god, Gruumsh's honor meant he stood by and allowed Talos to do what he desired.