Question about heritage and genealogy. Please help.?

Question:

Question about heritage and genealogy. Please help.?

My question is, do all surnames lead back to a common heritage/ place of origin regardless of where the ancsetors scatter to. I am confused as to what ties there are between some information that I have found about my last name Gilbert. I have found my Gilbert family dates back to decent from Cornwall England. Also, I have learned that the Gilbert family name is a sept of the Buchanan clan from Scotland. My coat of arms matches that of a website where I learned this information. http://www.houseofnames.com/xq/asp/s.gil...
Origin.EN/sId.844C425A-CFF2-4B...
Here is what I think, my direct anscestors are from Cornwall, England. After this, I feel that information is to hard to find about the direct lineage of my heritage after this point except for the origin of the Gilbert's which is from Scotland. Is this a reasonable assumption.

Additional Details

2 months ago
well the coat of arms is not mine it is owned by my grandfather I just recognized the same image online

Best Answer - Chosen by Asker: 2 months ago
well the coat of arms is not mine it is owned by my grandfather I just recognized the same image online