Which acoustic cues can be used by listeners to identify speakers’ linguistic origins in foreign-accented speech? We investigated accent identification performance in signal-manipulated speech, where (a) Swiss German listeners heard native German speech to which we transplanted segment durations of French-accented German and English-accented German, and (b) Swiss German listeners heard 6-band noise-vocoded French-accented and English-accented German speech to which we transplanted native German segment durations. Therefore, the foreign accent cues in the stimuli consisted of only temporal information (in a) and only strongly degraded spectral information (in b). Findings suggest that listeners were able to identify the linguistic origin of French and English speakers in their foreign-accented German speech based on temporal features alone, as well as based on strongly degraded spectral features alone. When comparing these results to previous research, we found an additive trend of temporal and spectral cues: identification performance tended to be higher when both cues were present in the signal. Acoustic measures of temporal variability could not easily explain the perceptual results. However, listeners were drawn towards some of the native German segmental cues in condition (a), which biased responses towards ‘French’ when stimuli featured uvular /r/s and towards ‘English’ when they contained vocalized /r/s or lacked /r/.