A number of people have requested this, so, with as few spoilers as possible, here is a guide to Who's Who in the interaction between MASH and Highlander in my stories.
Immortals - A secret race/species of human who, after their 1st physical death, do not age. Also, any minor non-head wounds heal instantly, and any death which does not involve decapitation is shaken off. They are compelled to fight one another to the death (Beheading) using swords, in a "Game" with rules that, for the most part, even the most evil of them abide by. The only two hard-and-fast rules appear to be : All duels are one-on-one, and that NO fights may take place on ground that is held to be sacred. All Immortals are parentless foundlings, their true origins unknown. They are also barren. This is a vast oversimplification of a hotly debated topic, so seeking an HL FAQ is highly recommended.
Watchers - An even more secret group of mortals whose task is to record the long lives of their charges for posterity. They are charged to watch, but never interfere with and never get involved with their charges. If this sounds easier said than done, there is a reason for that....
Macleods - Connor Macleod was born in The Highlands of Scotland in 1518. Dying in 1536, he came back to life and was cast out by his superstitious clan. Trained by Juan Ramirez and stalked by the powerful Kurgan, Connor saw the cycle repeat itself in the 1620's when Duncan Macleod was cast out upon rebirth. With the student now the teacher, a clan bond helped the two to help one another. Both are referred to as the Highlander, but only one is the true one. Go ahead and ask them which one, please. They are among the most powerful Immortals on Earth, though even Connor is a relative youngster compared to some. Connor is an active part of the Game, while Duncan adopts a more defensive mode. While Connor has taken out more powerful opponents, including, in 1985, the Kurgan, Duncan has recently withstood a six-year assault from a variety of foes, many of whose dishonorable methods netted them a high head count, now Duncan's.
Richie Ryan/Redstone - Duncan's protege until 1996, when an enemy had destroyed Duncan's ability to reason temporarily, causing him to kill Richie. Hopefully, his new protege does a little better.
Amanda - To call her Duncan's girlfriend will probably get you in a bad position. To call her a thief is far too simple. She is Duncan's friend and sometime lover, and she is a Master Thief, even once taking a mortal apprentice named Selina Kyle. (Sometime Down The Road, I Promise) Her amorality and freewheeling nature are friction/attraction between herself and the straightlaced, chivalrous Macleod. Just where is their relationship headed? Amanda is 1000 plus, though her maturity level doesn't always show it.
Methos - The Oldest Of The Immortals, easily 5000 years old. He has been both sinner and cynical saint. As one of The Four Horsemen, he was a monster. Now, he hopes that, through association with the heroic Macleod, somehow he can begin to expiate his sins. He has talked Duncan down from his high perch on numerous occasions, astounded that someone of 400 years can often be so naive about the world. Now, someone arguably even more naive will be Duncan's protege. Can the cynic help this one keep his head? Always in the back of Macleod's mind concerning Methos is the fact that not even his Horseman brothers were wise to trust him. In 1903, Methos, under the name of Abel Adams, married wife number 68, Mary Ingalls Kendall, daughter of his friend Charles Ingalls. He became adoptive father to the 2nd boy named Adam Kendall, Jr., as well as to Mary's brother Albert, who is also an Immortal. Colonel Kendall was the first CO of the 8063rd MASH, where his stepfather served in Korea as a surgeon under the name Cain Adams. Today, Methos is known as Adam Pierson and Albert as Charles Pierson. He works, ironically enough, as a Watcher.
Joe Dawson - A Vietnam Vet, Joe was inducted into the Watchers and has risen to be a major leader within the organization. He has the privilege and honor of watching Duncan Macleod. Problem is, he also epitomizes everything a Watcher is not supposed to do. He is near-best friends with his charge, helps him out where he can, and sometimes expects help back. Joe has been accused of revealing the Watchers' existence to Immortals. This is mostly untrue. Methos has known of them for centuries, and at least one Watcher practically adopted a young Immortal in grief over her lost son. Further, it was not any action of Joe's that led him to speak freely to Duncan. Sensing a growing movement against Immortals within the Watchers, spearheaded by Joe's Brother-In-Law, James Horton, someone decided to move against these Hunters by sending an ancient Watcher diary to Immortal Priest Father Darius, who in turn sent it to Duncan. This was just before Horton and his men killed Darius. Since no other Immortal was present, all of Darius power and wisdom and grace was lost--forever? Together, Joe and Duncan stopped Horton and his crew--forever?
Henry Blake - Technically, he was the first Highland Immortal, being the founder of Glenfinnan Town circa 750-800 AD. Also known as Sir Bedivere, First Knight Of King Arthur's Round Table. For all that he accomplished, life often left him befuddled. This feeling carried through to 1950, when he built and was the first CO of the 4077th MASH. Despite the Chaos, the place ran, and lives were saved. Refusing to take orders from shadowy forces within our government, Henry was killed on his way home from the war by the young man today known chiefly for his opposition to FBI Agents Dana Scully and Fox Mulder. He took a young pre-Immortal under his wing, while at the 4077th, and their relationship was often like that of father and son.
Sidney Freedman - Once called Soolaimon-Bar-Moshe, he was first killed along with his wife and her children by Kronos of The Four Horsemen during the Slaughter Of The Innocents. For years, he blamed the true target of that search, Yeshua-Bar-Yossef, known to his Greek followers as Jesus Of Nazareth. (For the record, my stories keep the mystery of faith; Christ was Not an Immortal; No proselytizing here, just my point of view. I believe he was who the Bible said he was. This does not have to be your point of view; This story is just that-a story) Later, though, he gave up wanting vengeance on this man, at the urging of Methos, who had left the Horsemen some 50 years prior. Seeking knowledge in the mysteries of Kaballa, he became quite powerful. Eventually calling himself Siddig-Ben-Moshe after his first great teacher, he settled in Prague and became Kaballa-Master for all of the Eastern World. In the 1880's, as Sidney Freimensch, he met and became a student of one more teacher-Sigmund Freud, who talked Henry Blake out of a blue funk. In the late 1940's, he entered the American Military, and served as a psychiatrist in the Korean Conflict. At the urging of Henry Blake, he cast a spell masking the presence of a pre-immortal. Becoming mentor to this Immortal upon his awakening, Sidney did his best despite a sorely lacking sword-arm. In 1994, he was killed by Horton's men, allied with renegade Immortal Xavier St. Cloud
Father Francis Mulcahy - The Watcher to 3 Immortals in Korea, and the person who sent Father Darius the Watcher Diary. As Bishop of Saint Louis, this good man died in 1989. But did the Padre have another secret?
General Sam Flagg - Renegade Watcher and Horton's mentor, extremely bigoted against Immortals, and instigator of Sidney Freedman's death. Called a "Strutting Poltroon that real spies used for cover" by Cigarette Man, Flagg was in fact quite a dangerous man--til 1996, that is.
The Pierces - Margaret Houlihan and her husband, Benjamin Franklin Pierce, are old friends of Clan Macleod. Hawkeye worked for Connor in Med School, and Duncan and Margaret once had an affair. But surely, the Pierces are in their 70's, now----Right!?
Benjamin T. Blake/Walter O'Reilly - Our hero. In the end, There Can Be Only Radar.