Suppose Leonard Lowe was a historical figure in a social or political movement. Then we would study the history of that movement, including the people involved, the events that took place, and the impact they had. We could look at primary sources such as pamphlets, letters, or speeches related to the movement to find out more about Leonard Lowe's part in it.
If Leonard Lowe was a historical figure in a particular field, say medicine or art, we could research the history of that field during his time. We might find mentions of him in textbooks, biographies of his contemporaries, or in the records of institutions related to that field. For instance, if he was an artist, we could look at the archives of art galleries or museums that might have exhibited his work.
Again, without more information it's hard to say. But if he was a historical figure, we could look at historical documents like newspapers from the relevant time, official records, or memoirs written by people who lived during that era. For example, if he was involved in a war, military records might give us some clues about his role and story.