This (above) inverted boat-profile crossguard (or lower guard) of cast bronze with incised appearing knot-like ornamentation is characteristic of the Petersen (1919) type "O", and the Geibig (1991) Kombinationstyp 9, associated with the period 900 to 950 by both authors. The illustration of a sword hilt to the left from Petersen (1919), figure 104, depicts a sword presently in the Universitetet I Oslo Oldsaksamlingen, accession C.13848a, found at Vestre Berg, Løten, Hedmark, Norway (a color photograph, frame/item reference 771, of this sword is on the World of the Vikings compact disc or laser disc, as is a photograph of another with a similar bronze hilt from the Tromso Museum, Ts.3592, found at Borge, Vestvågøy, Nordland, Norway, frame/item reference 5679.) Though missing from our present example, the upper guard would be expected to also have been of bronze and to have had five lobes radiating slightly out from the top of the upper guard.
A loose (that is, without remaining associated blade) cast bronze cross-guard with similar incised knot-like decoration (but with five hairpin-turnbacks between the complex ornaments instead of eight) was found in what is now northern Germany, just south of the present Danish border, in Sierksdorf, and is presented in Geibig (1991) as catalog number 317 (table 161, #8).
Even more intriguing is a small upper guard (with three hairpin-turnbacks between the knot motifs) found in Haddebyer Noor, accession 13018 in the Wikinger Museum Haithabu (just outside of Schleswig, Germany), and located in case 11.4 which explains and illustrates casting techniques (see an edited photo of the relevant part of this exhibit to the right and below; I presume the mold and one of the castings are replications), and illustrated in Geibig (1991) as catalog number 274 (table 155, #4) and in Geibig (1989) as sword #21 (table 2, #11). This was found as an isolated artifact retaining flanges from the casting process where the two halves of the mold joined, that is, appearing never to have been been finished with a file. This suggests that this hilt component was never mounted on a sword and is either an incomplete fabrication never finished or an abandoned flawed casting which escaped recycling. Geibig (1989) notes (p. 257 - 258) that more swords and sword hilt parts have been found at Hedeby than at the sites of other costal trading centers of the Viking Age and postulates that the presence of numerous unfinished objects and isolated hilt parts at this site suggests that craftsmen here likely produced hilts and mounted hilts of diverse origins upon sword blades. Thus, on the basis of this evidence, one may wish to speculate that the present sword was refurbished at Hedeby in the first half of the 10th Century.