My midwife told me, and my health visitor later said the same, that 'sleep promotes sleep'. For my two, this proved to be true.
Also, tired children don't eat well and then hunger wakes them. The only times I really tried to restrict or delay or change their spontaneous timings of naps was when the Cubs were 'phase shifting' from, for example, typically three naps to typically two, or typically two naps (one am one pm) to generally one (which they would, if you weren't a bit proactive about it, take at lunchtime and then be crabby and hungry and tired all afternoon). The other classic with the EldestCub was the few months at around the age of three when he would happily go all day without a nap but tend to fall asleep at teatime with unpleasant repercussions for one's evening. My 'management' of all this consisted of shifting mealtimes a bit to accommodate (lunch a lot earlier for a while, for example) and to be judicious in the use of pushchairs on busy days to encourage getting a few Zzzzs at more convenient times - and discourage it at 5ish o'clock when on the way home from a day of playing.
The SmallestCub started at nursery at around one, much younger than his brother had, and was most disconcerted by regular nap times. As soon as he moved from the baby room to the toddler room he abandoned the idea completely - because he ain't daft and he quickly worked out that while all the other littlies were dozing, he could have all the nursery workers to himself to sit on his favourite people's knees to get read stories by them.