The Vendel Period, started 4 years later in 540ad seems to be tied to Theudebert of Austrasia/Metz, shortly after taking the throne from his father Theuderic in 534ad.
Theudebert son theudebald would die without an hair and his seat would pass to Chlothar Merovingian who weds Waldrada, but is forced to divorce by Bishops due to incest. Then pass from Chlothar, to his son Sigebert, and Sigeberts wife, Brunhilda. Sigurd and Brunhilda of Volsunga saga fame, whose father is listed as Sigmund rather than Chlothar. Possible confusion with Sigismund Burgundian killed by chlothars father, Clovis, known as Volsung. Chlothars son Chram's name is given to Sigmunds sword, Gram, called Balmung in Nibelungenlied. So some name confusions in later Eddas. The dispersal of Merovingian myths into Swedens Vendel Period among wolfings, and then to East Angles of Wuffingas clan where Beowulf is thought to have been composed, makes sense, with beowulfs tale including a few Merovingians in the background tale.
Vendel Period in Sweden among the East Geats in 540 is followed by Wuffingas of the East Angles starting kingdom in 571under Wehha and Wuffa, where Sutton Hoo burial is. Likely East Geats of the wolfing Clan, ruling over angles and bringing Vendel culture to England.
Beowulf mentions Theudebert killing Beowulfs uncle Hygelac around 515. Hygelacs brother in law, Beowulfs father Ecgtheow, having killed a Wolfing of the East Geats. With the Merovingians possibly siding with Wolfings against Hygelac and company.
What prompted relations between East Geats and Merovingians, idk. Possibly still the harsh winter and need for trade.