The title says it all - but I heard that NASA considered horizontal integration for the Saturn V couldn't be considered, as lifting the rocket to a vertical position would require an immense engineering effort to prevent sagging or damage while lifting, as well as simply moving such a large object into the launch position. So how / what mechanisms did the Soviets use to achieve this with the N-1, a similarly sized launch vehicle?
They used an extremely large rail-based transporter/erector nicknamed the "grasshopper".
This image shows the N-1 in the process of rotation.
russianspaceweb says the hydraulic ram visible in this image "boasted a hydraulic cylinder one meter in caliber, which had a length of nine meters and would extend up to 16 meters". Two pairs of these rams were employed per Grasshopper.
This page states that the Grasshoppers were rebuilt and used for the Energia/Buran.