In the collection of the Museum of Warmia and Masuria in Olsztyn, there is a Roman provincial brooch made of copper alloy (Fig. 1). It was found in the northern suburbs of Zalewo in the County of Iława, NE Poland. Administratively, the area belongs to the village of Bajdy, located about three kilometres to the north-west. The artefact represents a group of brooches with two knobs on the bow (German Doppelknopffibeln), type 236 in keeping with Oscar Almgren, variant c according to a detailed study by Jochen Garbsch. Such specimens are characterised primarily by a frame-like foot and the construction of the spring mechanism in which the chord is held in place by a relatively narrow hook. Brooches with a double knob on the bow, the so-called winged brooches (Almgren 238) and characteristic openwork belt fittings are considered to be some of the main metal elements of Norico-Pannonian female dress. Almgren 236c-variant fibulae are indeed largely concentrated in the area of Noricum and Pannonia, although they are also known from Raetia and, in smaller numbers, from the northern parts of Italy and Dalmatia. Their local manufacture is confirmed by, for example, the casting moulds and partly finished pieces found at a Noric settlement in Magdalensberg, Carinthia. Fibulae of variant Almgren 236c are also very numerous in Barbaricum and indicate contacts, mainly of a commercial nature, with Roman provinces. According to recently published compilations, specimens representing this variant were present at more than 50 sites in several distinct concentrations: in the Czech Republic, south-western Slovakia and adjacent parts of Lower Austria and Poland (Fig. 2). North of the Carpathians and the Sudetes, Almgren 236c brooches are more clearly concentrated in the territory occupied by the Przeworsk Culture in central Poland, western Lesser Poland and right-bank Mazovia. The last large area of concentration is on the Lower Vistula River, at a few sites of the Wielbark Culture. The chronology of Almgren 236c brooches in the territory of the Roman Empire covers the entire 1st century CE. Such fibulae are found in contexts from the late period of Augustus’s reign to the rule of Trajan, although most of the assemblages do not date beyond the Claudian period, i.e. the middle of the first century. Even though Almgren 236c brooches are often part of grave-goods in the area of Barbaricum, the number of precisely dated assemblages is, unfortunately, small. In the Czech Republic, these forms are considered to define stage B1b after Eduard Droberjar, corresponding in absolute chronology to 20/30–40/50 CE, or, more broadly, late phase B1 of the classical (Czech) eye brooch horizon up to 50/70 CE. In the areas north of the Carpathians and the Sudetes, Almgren 236c fibulae should also be dated to the mature stage of phase B1. According to the studies carried out so far, the northern part of the Iława Lakeland in phase B1 was part of a vast deserted area separating the territories occupied by the populations of the Wielbark Culture on the Lower Vistula and the Nogat, of the Przeworsk Culture in Northern Mazovia, of the Bogaczewo Culture in Masuria and of the Dollkeim-Kovrovo Culture in Sambia (Fig. 3). The site where the Bajdy fibula was discovered is closest to the Wielbark Culture settlement, south of the ancient bay of the Vistula Lagoon, whose remnant is the present-day Drużno Lake; it lies about 20 km by air from the Święty Gaj cemetery and the remains of a dyke in Bągart. The Almgren 236c brooch from Bajdy, together with a recently discovered and yet unpublished Almgren 18b fibula from nearby Przezmark, as well unpublished Almgren 53 fibula from Jawty Wielkie, is the oldest trace of penetration of the northern part of the Iława Lakeland by the people of the Wielbark Culture. These episodes should be dated to the phase B1, i.e. several decades before regular settlement activity of the Wielbark Culture in phase B2b, which led to the occupation of extensive areas of the Iława Lakeland, the Warmian Plain and the western edge of the Olsztyn Lakeland, reaching roughly up to the longitudinal line of the Pasłęka River.