You can reasonably expect most recipes to include directions on both the temperature that your oven should be at and the length of time it should take for the goods to be optimally baked. It wasn’t always so. The gas and electric oven-cookers we are familiar with today are a relatively recent innovation. Back when most domestic baking was done in cast iron ovens heated by burning coal or wood, fine temperature control was unheard of, and recipes were correspondingly approximate. Variations on the phrase ‘bake in a hot oven’ are commonplace even in cookery books of the early to mid 20th century, even though ovens regulated by thermostat were by then very widespread: people’s habits often lag behind the technology available to them. Nonetheless, people got along fine for thousands of years without the convenience of the temperature dial.
That being the case, it’s logical to deduce that the temperature at which we bake something is not crucial to within a few degrees; far from it, in fact. Generally speaking, this is true. A loaf baked at 200°c may not be the same as one baked at 240°c, but they shouldn’t be all that much different, either, though the former will take a little longer than the latter. Authors of recipes (myself included) usually stipulate a particular temperature because it is expected of them, rather than because failure to maintain a particular temperature will end in ruin. In times past, it was enough to talk about low, medium and high and get away with it (if you own an AGA or similar cast iron range this is still sufficient, of course, because traditional ranges have very limited temperature controls).
This is probably just as well, because oven thermostats aren’t always very reliable. It’s common for them to be less accurate at some temperatures than others, and they lose accuracy over time. An oven thermometer is a useful piece of kit for the baker, and is essential if you want to recalibrate a thermostat that is seriously out of whack.
As far as bread is concerned, 200-250°c is an acceptable temperature range within which to bake. Dough enriched with eggs, hard fat and/or sugar will brown more quickly, and at higher temperatures the crust can burn while the inside remains raw. These are better off baked at the lower end of the scale, while most other types of bread will benefit from higher temperatures; I would suggest 220°c as the preferred minimum. More important than the precise temperature is boosting your oven’s thermal mass – its ability to absorb and store heat. This is a topic in its own right, and one I will probably return to in due course. In the meantime, you can get the full story here.