I'm confused. I would have used "war" instead of "waren" based on the fact that the subject ("das Thema") is singular, even though the subject complement ("die Höhenmenschen") is plural. Is there an error in the above sentence or does the grammatical rule in German state that the linking verb "sein" is conjugated based on the subject complement and not the subject?
Conjugation of the linking verb "sein" with a subject and subject compliment

PaulS108
October 28, 2020
I'm confused. I would have used "war" instead of "waren" based on the fact that the subject ("das Thema") is singular, even though the subject complement ("die Höhenmenschen") is plural. Is there an error in the above sentence or does the grammatical rule in German state that the linking verb "sein" is conjugated based on the subject complement and not the subject?

sfpugh
October 31, 2020
I understand the sentence is correct. There was a thread about just this a while ago. As you suggested it is “waren” because “Höhlenmenschen” is plural.

Julia-Rocket-German-Tutor
November 2, 2020
Guten Tag PaulS108 und sfpugh,
Yes, the sentence is correct, you can see the thread with the explanation that sfpugh has mentioned above here:
https://app.rocketlanguages.com/members/forum/german/german-grammar/194-das-thema-der-ausstellung-waren-die-hoehlenmenschen-why-is-waren-plural
Viele Grüße,
Julia

PaulS108
November 3, 2020
Thank you for the explanation in the thread. Interesting that sfpugh and I were both confused by the same sentence.
2 years ago when this thread appeared in the Forum, sfpugh pointed out that a short explanation in the lesson would have been helpful in avoiding the confusion. The response to him at the time was that his feedback would be forwarded to the Course Development Team.
For whatever reason that his suggestion was ultimately not implemented in the lesson, in light of fact that the same confusion has again arisen, I wish to reinforce sfpugh's suggestion for the sake of future German learners.
Regards,
PaulS108

Julia-Rocket-German-Tutor
November 16, 2020
Hallo sfpugh und PaulS108,
Thank you for your feedback and suggestions! We have added a literal translation to help clear things up.
Grüße,
Julia