Captain Malcolm was born on September 8th 1733 in Nottingham, England.
Pearson and the Dawn Malcolm
After helping Pearson recover his first Chart, Pearson repays him by raising the Gideon and rechristening it the Dawn Malcolm in his honor, gifting it to him on the condition that he join Pearson on his quest to recover the other Charts. Malcolm accepts and the two round up the first, all-human crew of the Dawn Malcolm.
After a dangerous first voyage off-world, Pearson takes Malcolm and the Dawn Malcolm without crew to the Manifold. There they negotiate with the Denizen council to try to get permission to make the Dawn Malcolm itself a Chart. They are denied this, but recognizing the Dawn Malcolm's limitations, the council works together to cast a spell over the ship. Under this spell, any material made into its structural support will maintain the scientific properties it has on its native world.
By the time Wayne Wright finds himself aboard, the Dawn Malcolm has been sailing for ten years under Captain Malcolm, and the crew has expanded to include the very unique, otherworldly characters, including Germck and his entire tribe.
For violating his sentence, Pearson and Malcolm are brought before the Denizen High Council immediately after Malcolm's conversion. After a lengthy trial without pause (Denizens don't need to eat or sleep for many Earth days and a living Chart never has to eat, drink, or sleep), Pearson is thrown into Hell without a Chart, and Malcolm is charged with finishing Pearson's work himself in order to legally free Pearson. Between this time and his appearance in the Mist arc, Malcolm slowly grows accustomed to his new form. He masters the abilities he knows from using Charts and realizes many new ones he learns come from completed Atlases.
With his new incredible powers, an expanded mind able to comprehend the Manifold and all the worlds, and perfect immortality, something not even the Denizens could achieve for themselves, Malcolm becomes increasingly aloof. Without any fear of death, he begins to understand what really makes life worth living, and he realizes that no sapient civilization truly values those aspects. So Malcolm increasingly meticulously goes about his work of finding the remaining Charts and Atlases. All of his interactions with sapient creatures during this time period can be characterized by Malcolm speaking and acting from sight beyond the comprehension of anyone else he's involved with, and thus a gradual disconnect leading to outright hostilities spawn from the other parties near him. Needless to say, centuries of this have a profound effect on Malcolm
Age of Mist and The Pearson Twilight
By the time his existence reveals itself again, hundreds (if not thousands) of years have gone by, and the Earth and all humanity has since converted to mist. Malcolm's refusal to join and his unusual ability to reject conversion makes him stand out in human society. He responds by purchasing a small starship, naming it the Pearson Twilight, and leaving Earth with a small human crew in search of the last few Charts that he believes have made their way among the stars.
Whether or not Malcolm ever dies is never discovered. Since he was made a living Atlas, he was perfectly immortal, unable to sustain damage and able to survive vacuum without harm. However, any denizen has the power to turn a living Chart or Atlas back to its previous form, so Malcolm could still have been made human and then killed. Common knowledge suggests that his greatly extended lifetime would have given him the insight necessary to sustain existence in Annwyn, and that his lack of appearing there by mortal methods means that he has not yet died. Some may counter that the purpose of Sheol is to give insightful mortals more time to discover their sought-after higher existence, and Malcolm has had hundreds (or thousands) of extra years and may have discovered this without Sheol's help. Therefore he could still die and not make his way to Hades.