Lord

"So what happens now? Do I have to wear a funny hat or something?"

- Ike, about to be promoted to Lord in Path of Radiance.

The Lord (ロード Lord, called Junior Lord in Fire Emblem: Genealogy of the Holy War) is arguably the most important class on the battlefield. In every Fire Emblem game, except in Fire Emblem Gaiden, Fire Emblem: Radiant Dawn, and Fire Emblem: Fates, the Lord class will represent the player's main character(s), whomever they may be. Unlike other classes, Lords have no real generalization, as their unique styles and abilities change depending on which Lord(s) is featured within the game. It should also be noted that should the player's Lord be killed on the battlefield, it is an automatic Game Over.

Combat
Players are forced to bring the Lord onto the battlefield for every fight. While it is incredibly important to protect the Lord to avoid an instant defeat, one should not keep them on the sidelines while their other characters do the work. While initially frail, upon reaching higher levels, Lords are capable fighters and gain access to unique and powerful weapons. For this reason, it is beneficial that their skills be appropriately leveled when taking on the later enemies and bosses. They generally wield swords, but there are exceptions (Eg: Hector and Ephraim). Because the Lord class and characters tend to change from game to game, no general strategy can be offered other than to find a way to make use of their abilities properly.

Promotions
Although every Lord is different, their promotions share the same trait. Different Lords are promoted to different Lord classes, each one specializing in their own fields of combat. Lord promotions are often reached by obtaining a certain level or using a special item after reaching that level, while other times Lords promote after certain events in the story. It should be noted that early Fire Emblem games do not have Promotions for Lords, the first game to feature this was Fire Emblem: Genealogy of the Holy War. In Fire Emblem: Thracia 776, Leif promotes to Prince (his class from Genealogy of the Holy War) upon retaking Leonster. In Fire Emblem: Binding Blade, Roy has his class changed to a Master Lord after receiving the Sword of Seals. In Fire Emblem: Rekka no Ken, Lords must be at least level 10 to use the Heaven Seal to upgrade to the next class. In Fire Emblem: The Sacred Stones, both Lords are given the option to use the Solar Brace/Lunar Brace to become a Great Lord.

Gaiden
There is no lord class in Fire Emblem Gaiden. Alm is technically a Fighter, while Celica is a Priestess.

Path of Radiance/Radiant Dawn
In Path of Radiance, Ike is the clear-cut Lord character, but is the first Lord character that is not of noble birth. However, throughout the course of the game, he is introduced into nobility, and this event marks his promotion to Lord proper. Notably, Ike is the only Lord character to promote into the class rather than have it as a base class.

In Radiant Dawn, just like in Gaiden, there is no Lord class; however, the characters who fulfil the role of a standard Lord character are Micaiah (a Light Mage/Light Sage/Light Priestess) and Ike (a Hero/Vanguard in Radiant Dawn), while Elincia, Geoffrey, and Tibarn serve as temporary leaders (notably, Geoffrey can seize in one of his chapters).

Awakening
Chrom is the main Lord of Awakening and his daughter, Lucina, is also a Lord. Unlike previous games, their promotion is not tied to the plot, and they can become Great Lords at any time by using a Master Seal. While Chrom can have a second child in the game, neither his other potential daughters nor three potential sons will inherit the Lord class. Nonetheless, all of his daughters will inherit Aether while his sons will inherit Rightful King. Lucina, if she is the mother of female Morgan, will also not pass down her Lord class to Morgan, but will pass down Aether like her father does.

Fates
Fates is the third game in the Fire Emblem franchise that lacks a playable Lord class unit. The Avatar of Fates is a Nohr Prince/ss and is treated as the main Lord of the game.

In the Awakening DLC, the Lord Class cameos as an NPC class used by Chrom, an allied unit.

Trivia

 * Through hacking in Genealogy of the Holy War, one can see that the ability to seize a castle is not locked to the main character. Anyone can seize a castle, as long as they are of the Lord class, so it can be assumed that seize is actually the hidden class skill of that class.
 * As noted above, every single Lord in Fire Emblem has been of noble birth, except for Ike. He was given a noble title and powers, and it was only then that he was promoted into a Lord. This also gives Ike the distinction of being the only main character that promotes into a Lord. After the game, he rejected any offers of peerage, thus the Lord class was lost to him in the next game.
 * With the exception of Lyn, every character in the Lord class wears a cape.