Every Monday we will post an entry that hasn’t yet been published with a view towards harnessing the collective onomastic power of the internet. If you have any thoughts about the name’s origin, other variants it might be related to, other examples of its use, etc., please share them in the comments! If you wish to browse other Mystery Monday names, there is an index.
Today’s name is a curious feminine name from Latvia. We’ve rather punted on the standardized/normalized form: We have no idea whether the name does in fact include rebecca, etymologically, or whether this is a false friend.
The context makes it clear that this is a feminine name, which is why we think rebecca may be a player in the analysis here, but another alternative is that the -(e)ke ending is simply the standard Low German diminutive suffix. In which case, the root name would be something like Bulreb(e) — which, we have to confess, is entirely opaque to us.
Have any thoughts on what this name might be? Please share in the comments!
Dictionary of Medieval Names from European Sources 
This sounds like a Low German surname to me.
I identify the suffix -bek that is frequent in place names. As a candidate place name I see Bullerbek attested as a Flurname (field name) in Grevesmühlen, Mecklenbug-Vorpommern, Germany. There is also a city named Billerbeck near Münster in Nordrhein-Westfalen, Germany.
This sounds like a Low German surname to me.
I identify the suffix -bek “brook, beck” that is frequent in place names. As a candidate place name I see Bullerbek attested as a Flurname (field name) in Grevesmühlen, Mecklenbug-Vorpommern, Germany. There is also a city named Billerbeck near Münster in Nordrhein-Westfalen, Germany.
When you can read German, this blogpost about possible meanings of buller in the name of a brook named BUllebeck is also interesting:
https://christofspannhoff.wordpress.com/2015/05/
My reaction is the same as Jörg Kappen’s. And while it’s geographically a bit removed from Riga, I note that Roger Wilmans, Die Urkunden des Bisthums Münster von 1201-1300, Nr. 1635, dated 15 April 1299, mentions a Johanne (abl.) de Bulrebeke, showing this spelling of the locative.
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