As everything else, gold price is determined by supply and demand. However, it is also affected by the US Dollar exchange rate, because it is priced/Quoted in Dollars. If the Dollar rises in the forex market, gold prices tend to drop and vice versa. (Oil prices are similarly affected).
In view of the current turbulent economic and political times, some have opted to switch part of their assets from equities or fiat currencies to solid assets such as gold. Russia and China have been doing it for quite a few years and have accumulated hundreds of billions worth of gold.
Despite that, gold prices have been stuck for a couple of years in a range between $ 1340 to $ 1200 per ounce. The low was at $ 1061.98 in Dec 21, 2015, and more recently around $ 1160 – 1175 in August 2018. The highs were at $ 1361.09 on June 28, 2016 and more recently $ 1350.70 on April 9, 2018.
Obviously, the strong dollar (i.e. the weak other world currencies) have kept the dollar rate high and stifled the rise of gold prices.
More recently however, the Dollar slipped slightly last Friday (Sep 7th), probably as the trade wars got more intense and are now heading towards Japan. Immediately gold reacted upwards and is now ranging between approx. $ 1196 and $ 1200. (We may see a similar small rise in oil prices as well).
This may be a temporary rise, especially as the US Fed is already making positive noises about another interest rate rise probably followed by another this year. Nevertheless, as the world economic and geopolitical wrestling tournament continues to build up, gold is likely to play a major role, and it may be worth your while to monitor it closely.