General

Generals are the promoted versions of Knights. They have excellent defense, good attack, surprising evasive ability for their size and bad resistance. They are quite slow, but what they lack in maneuverability they make up for with defensive and offensive ability. Many of the bosses in several games are generals (or their lesser form earlier in the game)

Combat
Generals can be used like "walls" to block enemy forces and are quite useful in survival and defense objective battles. They can be used to block small entrances to prevent opposing units from getting past them, this is very useful if you wish to stop theives from escaping. A General's weaknesses are magic and anti-armor weapons, as well as fast moving durable and powerful characters like Heroes, experienced Paladins and Warriors.

The rarity of a general ever being out matched on the field through sheer brute force is high, which means they are very valuable to any team and their durability is very helpful to weaker units as they can hide behind them. Another thing that helps Generals is they gain the ability to use bows which can deal with Mages slightly but you shouldn't risk using a bow to completely destroy one (Unless you are using something like a Killer Bow or Parthia, neither of which are very likely due to their high weapon level)

In Radiant Dawn, Generals can Promote to Marshall, greatly improving most stats.

In WiFi battle, Generals suffer greatly for their low speed cap. Although their high defense means they can survive even four hits from a swordmaster, they cannot survive being doubled by a Berserker or Sage. They lack high movement, and are affected by weapons like Armorslayers. Individually, these flaws can be addressed by cards, but combined they cannot. Generals have high attack, and can use bows. Using a General often means leaving the fate of a battle in the opponent's choice of squad. If a General is placed up against a Swordmaster, and the Swordmaster does not have an Armorslayer, the battle can be quite even (especially using cards like Fleet Feet). However, due to the relative ease of counter-picking teams to beat Generals, it is difficult to use them reliably on WiFi.

Weapon Usage
Generals have been in every Fire Emblem game to date, and have had varying weapons available for them. This chart shows the differences.

Seisen no keifu

 * HP:80
 * Str:25
 * Mag:15
 * Skl:21
 * Spd:20
 * Luck:30
 * Def:27
 * Res:18

Path of Radiance

 * HP:60
 * Str:29
 * Mag:20
 * Skl:27
 * Spd:24
 * Lck:40
 * Def:30
 * Res:25

Shadow Dragon

 * HP: 60
 * Str: 27
 * Mag: 20
 * Skl: 25
 * Spd: 21
 * Lck: 30
 * Def: 30
 * Res: 20
 * Lance: A, Bow: A

Skills
In Fire Emblem: Seisen no Keifu, Fire Emblem: Thracia 776, and Fire Emblem: The Sacred Stones, Generals have the skill Great Shield.

In Fire Emblem: Path of Radiance, generals can learn Luna as their Occult skill, while in Radiant Dawn they learn it automatically when they promote to Marshalls.

Ankoku Ryū to Hikari no Tsurugi/Shadow Dragon

 * Lorenz
 * Horace
 * Emereus
 * Harmein
 * Zharov
 * Hollstadt
 * Jiol
 * Dactyl
 * Larissa

Possible promotion for: Draug, Macellan, Dolph, and Roger

Monshō no Nazo

 * Sheema
 * Lang
 * Possible promotion for: Draug

Seisen no Keifu

 * Hannibal

Possible promotion for: Arden

Thracia 776

 * Xavier
 * Possible promotion for: Dalsin

Fūin no Tsurugi

 * Douglas
 * Hector
 * Murdock

Possible promotion for: Bors, Wendy, and Bath

Rekka no Ken

 * Darin
 * Murdock

Possible promotion for: Wallace, Oswin

The Sacred Stones

 * Vigarde
 * Tirado
 * Fado

Possible promotion for: Gilliam and Amelia

Path of Radiance

 * Tauroneo

Possible promotion for: Gatrie and Brom

Radiant Dawn

 * Tauroneo
 * Brom
 * Gatrie

Possible promotion for: Meg

Fire Emblem: Shin Monshō no Nazo ~Hikari to Kage no Eiyū~

 * Macellan
 * Dolph