This is the 5619th most frequent Russian word.
появлялись
"Appeared" or "emerged."
In this sentence, "появлялись" is used in the past tense to indicate the emergence or arrival of beings in a specified location.
В далёких краях появились удивительные существа.
In distant lands, astonishing creatures appeared.
Here, "появлялись" describes a recurring action in the past, indicating something that happened repeatedly over time.
На горизонте иногда появлялись корабли.
Ships would occasionally appear on the horizon.
In this context, "появлялись" conveys a past event where lights came into vision or appeared in the night.