Description

A very rare shortsword from Sumatra. The dramatically shaped blade has a straight spine with a sudden downward slope with a back bevel. The edge side starts narrow and widens considerably towards the top half. In profile, the blade resembles the piso salanenggam of the Batak.

A notable difference is the engravings: The blade's sides are both finely engraved, and the engravings stand out over a deliberately blackened background. Such blades are not described by any period ethnographers.

The hilt is carved from black buffalo horn, in the shape of a heavily stylized makara. The unusual scabbard follows the shape of the blade, save for a large sideways protrusion at the top. The scabbard is open at the top to allow the very wide blade to come out.

Attribution

The Ethnographic Museum in Leiden has a very similar sword in similar scabbard under accession number RV-1599-599. It was purchased by the museum in 1907 and was attributed to the Mandailing people. Looking at the scabbard's profile, the blade must be narrower than ours.

Leiden Ethnographic Museum accession number RV-1599-599.

Another, acquired in 1910 is held under accession number RV-1752-36. Similar in that is, too has this narrow scabbard that must have a back slot like outs. The hilt is rather different, though.

Leiden Ethnographic Museum accession number RV-1752-36.

A sword with a very similar blade, but a different hilt, is in the collection of Michael Marlow. It is described in detail in Steel and Magic, Edged Weapons of the Malay Archipelago.¹ He attributes his to the Mandailing of West Sumatra, based on a piece in the Leiden Ethnographic Museum with a near-identical hilt.²

The Mandailing are a people that are part of the Batak Ethnolinguistic group but have converted to Islam somewhere in the 18th or 19th century.

This example shares a very similar blade to Marlow's example, while the hilt and scabbard are strikingly similar to RV-1599-599 in the Ethnographic Museum in Leiden.

Comparison

In the below picture, I compare the sword to two other, related swords in my current inventory:

In the middle we have another Mandailing sword, with a hilt very similar to the Marlow example, albeit simpler in execution. The blade is very similar to this sword, up to the fine rope-like engravings.

At the very bottom, another rare Sumatran sword, its hilt much closer to the piece that is discussed in this article but more detailed in execution. There are also some notable differences in the blade, which is forged in a hairpin style with no engravings and a much shorter backedge.

Conclusion

A rare and possibly unique sword from Sumatra, with a fine engraved blade of a type that is also seen on at least two swords that may be attributable to the Mandailing people.

Notes 
1. Sixt Wetzler, editor; Steel and Magic, Edged Weapons of the Malay Archipelago. Catalog of the Solingen Klingenmuseum Exhibition that ran from 1-12-2019 to 30-6-2020. Deutsches Klingenmuseum, 2020. Pages 50-51. 
2. It is kept under accession number RV-769-23. It was gifted to the museum on March 1st, 1890.