Efforts undertaken until now to establish the dating of the end of phase B2 and the onset of the Younger Roman Period, using mainly finds from the territory of the Przeworsk culture, have at present become, to some extent, outdated. This has happened as a result of progress made in the study of the places of production of individual terra sigillata wares and the dating of the activity of workshops producing this pottery, and even more so, as a result of a significant increase in the number of source evidence. This last observation applies most of all to Przeworsk culture, now with a record of 92 closed assemblages containing terra sigillata, originating from 33 sites (Fig. 1). This is more than twice the number available at the time of the start of earlier studies addressing the absolute chronology of the phases of the Roman Period basing on terra sigillata present in grave inventories from the entire territory of the Barbaricum. New finds of terra sigillata from Przeworsk culture territory have not significantly altered the overall view of the influx of these imports, nevertheless some individual finds have come to light, originating from workshops not represented earlier in the record of terra sigillata wares in our study area. First of all, there has been a visible increase in the number of finds from the youngest wave of the influx of terra sigillata wares, produced during the 3rd century AD – mainly at Westerndorf and at Pfaffenhofen. The discoveries of terra sigillata made more recently in the Przeworsk culture territory did not bring new evidence for the chronology of the Early Roman Period. Neither did the study of this category of imports add much data useful for dating assemblages assigned to the so-called intermediate phase B2b–C1a (Fig. 1), i.e., assemblages that have their chronological position defined by artefacts found with markers of phases B2b and C1a. Terra sigillata discovered in these assemblages originates from workshops active in AD 140–170 at Lezoux (ALBUCIUS, CINNAMUS), at Rheinzabern (JANUARIUS I) or, during a slightly later period, AD 160–195 at Lubié (CASURIUS), or even in AD 175–210 at Rheinzabern. We have more data useful for determining the absolute chronology of phase C1a (Fig. 2). Only a handful of grave assemblages from this phase contain terra sigillata manufactured after AD 160, at Rheinzabern (CERIALIS II–III, CERIALIS IV, CERIALIS V, CERIALIS Towar B) or at Lubié (CASURIUS). It is notable nevertheless that the majority of these workshops, except for the workshop of CASURIUS at Lubié, continued to produce their wares over several decades, presumably, until AD 210s/220s. A similarly modest number of grave assemblages from phase C1a contain terra sigillata manufactured starting from AD 175 until 210–220 (Rheinzabern, group IIa: e.g., B.F. ATTONI; Westerndorf: COMITIALIS). A number of further grave inventories from phase C1a contain even younger wares, originating from the workshop of HELENIUS at Westerndorf, active in AD 200–230, possibly a little longer. Moreover, in the group of grave assemblages likely to date from phase C1a there are also two finds with terra sigillata produced by the potter HELENIUS who was active at Pfaffenhofen in the period AD 210–250. The largest group (more than 30 graves) are assemblages assigned to phase C1 but their dating cannot be refined further - either to phase C1a or to phase C1b (Fig. 3). Despite this they have some relevance for the dating of the origins and the time of the spread of the Younger Roman Period style. Only in a single case a grave dated broadly to phase C1, presumably its earlier segment, contained a terra sigillata vessel produced in AD 150–170 at Rheinzabern (FIRMUS I). Of the remainder nearly a half are inventories containing terra sigillata produced only between AD 175 and 210–220, some of them, even until 230. These are the wares from Rheinzabern (CERIALIS V, COMITIALIS V) and from Westerndorf (COMITIALIS). The same number of inventories dated to an unspecified segment of phase C1, contain somewhat later wares, with a dating of between AD 190/200 and 230s, and some, as late as AD 245/250 (Rheinzabern, group IIc: PRIMITIVUS I; Rheinzabern, group IIIa: JULIUS II – JULIANUS I; Westerndorf: HELENIUS). An analysis focused on the terra sigillata furnishes only limited evidence useful for establishing an absolute dating for the horizon of female graves defined as B2/C1 (Fig. 3). Their contemporaneity with phase C1a is confirmed by the inventory of the grave from Przywóz with fragments of terra sigillata produced in AD 175–210 (Rheinzabern: MAMMILIANUS), and presumably, also of grave 21a from Opatów, with a vessel datable to AD 160–210 (Rheinzabern: COMITIALIS SECUNDIN.AVI). Presumably, this would be the dating appropriate for the burial discovered recently at Morawianki containing a brooch, type A.V, 8 and casket mounts, basing on fragments of a vessel from the workshop COMITIALIS at Westerndorf, active in AD 175–220, and also for the feature 243 recorded in the settlement at Kraków-Mogiła which, next to a brooch type A.43, yielded a fragment of a terra sigillata vessel from the workshop B.F. ATTONI active in AD 175–210. A confirmation for the dating of forms characteristic for the female grave horizon B2/C1 (e.g., brooches type A.41) is supplied also by finds that have a dating based on the correlation with the events from the time of the Marcomannic Wars, e.g., those originating from the camp at Iža and those from a settlement feature in the locality Biely Kostol in western Slovakia. The extended period of activity of individual workshops producing terra sigillata makes it rather difficult to specify more closely of the relationship between finds attributed to successive chronological phases. This observation applies also to the correlation of phases C1a and C1b. The latter is represented in the investigated material by a small number of inventories (Fig. 3). They contain terra sigillata produced in AD 175–210/220 (Rheinzabern: B.F. ATTONI; Westerndorf: COMITIALIS) or AD 200–230 (Westerndorf: HELENIUS). From phase C1b comes also a number of grave finds with terra sigillata produced at Pfaffenhofen in DICANUS style, AD 230–260. Thus, terra sigillata finds confirm that artefacts recognized as typical for phase C1b were in use presumably already during the late 2nd century, or the first and the second decade of the 3rd century, contemporaneously with forms typical for phase C1a. Because, if we assume that the terra sigillata from AD 170–210/220 does not come from the final years of activity of the workshop which produced them, we have to accept that the find from Chorula confirms a surmise drawn on the basis of Roman iconography on the early appearance of some forms (in this case, shield-bosses with a hemispherical body and no collar), prior to the period of the spread of the style of phase C1b. This is shown by the sarcophagus from Via Tiburtina-Portonaccio, dating from AD 180s, with a depiction of a shield boss of a form corresponding to the find from Chorula. Drawing on the chronology of other imports, the onset of phase C2 has been accepted as coinciding with the early years of the second half of the 3rd century. Consequently, one may conclude that inventories with the youngest imports of terra sigillata, the wares of HELENIUS of Westerndorf and somewhat younger wares from Pfaffenhofen (HELENIUS, DICANUS), originate still from the final years of phase C1. These grave inventories, like the relatively abundant other wares from Pfaffenhofen discovered without a specified context, would be evidence of a much more intensive Przeworsk culture settlement during phase C1b, than might be concluded basing on the known finds of artefacts of a form recognized as markers of this phase. The number of currently known assemblages dated by terra sigillata vessels shows that, in determining the chronology of the closing stage of the Early Roman Period and the onset of the Younger Roman Period, our basis are mainly sepulchral Przeworsk culture assemblages containing this pottery. To some extent observations presented here relative to the dating of the onset and the duration of phase C1b find confirmation also in finds of assemblages with terra sigillata from the territory of the Wielbark culture. That our observations are correct is indicated also by the relatively modest number of closed assemblages containing terra sigillata from other regions of the Central European Barbaricum. In summary, we find that we have to distinguish two horizons within the early segment of the Younger Roman Period: a period when some forms, still not too numerous, characteristic for phase C1a, come into use, and a period when the style typical for this phase has become widespread. In Przeworsk culture the first of these horizons began during the third quarter of the 2nd century, although presumably not in its opening years, whereas the onset of the second horizon, proper for the Younger Roman Period, definitely ought to be dated to the last quarter of that century, most likely, its end, after the Marcomannic Wars. Less easily defined are two horizons of phase C1b: an older, partly still synchronous with phase C1a, presumably spanning the end of the 2nd century and the first two, possibly, three decades of the 3rd century, and a second horizon covering the remainder of the first half of that century. Thus, observations presented here confirm the view that the cultural change during the Roman Period did not unfold in leaps and bounds, and the periodization scheme used universally for this period reflects only a general sequence of successive stylistic changes and, as such, does not allow a closer absolute dating also of the finds which are recognized as characteristic for a particular phase. This has relevance for any attempts made to synchronize the findings from the analysis of archaeological sources with historical data, and also for the studies of the chronology of change in different areas of culture of the barbarian societies of the Roman Period.