"about" und "on" treffen das "über" m.E. am besten.

Vielen Dank. Hätte mich spontan auch für "about" entschieden, war mir aber nicht sicher.

@SaMiAi: paßt nicht ganz, da der komplette Satz wie folgt lautet:

übersenden wir Ihnen eine Chronik über die Firma XY sowie die Familie XY

company and family chronicle geht auch schlecht, da ich den Eigennamen noch unterbringen muss. Trotzdem vielen Dank - den Vorschlag merke ich mir auf jeden Fall :-)

Many company websites have a section entitled "Company history". Families also commission someone to write the history of the family.

Chronicle is far too archaic in this usage

Plenty of examples in Internet

Some say "time line", OALD gives timeline

Chronicle is definitely out -- as has been mentioned, it's too archaic, but also too limited in its use/meaning.
Timeline is tricky. A timeline has a very specific structure, typically
1922 Founding of the company by XYZ
1930 Company closed 90% of its factories due to the Great Depression
1989 Company expanded into the defense industry
2004 Company profited extremely from contacts with VP Cheney
2008 Company again closed 90% of its factories due to Bush's recession
...

A family timeline would be quite unusual.
Best to stick with "history".