Dry weather in the Americas and Western Europe, and the Covid-19 pandemic, had an adverse impact on food, fuel and other supplies and costs, causing high prices before the late February invasion. China's struggles with Covid added to global inflation and cost of living pressures.
After three months of war, about 22 million tonnes of grain and vegetable oils in Ukraine still cannot get out to markets around the world, and another harvest is soon due.
Ukraine and Russia normally supply a third of the world's wheat. Russia has put Ukraine's ports under blockade and Moscow is under Western sanctions.
Millions of people in dozens of countries rely on Ukraine's supplies getting through. Countries in the Middle East and Africa are particularly at risk.
David Beasley, the head of the UN's World Food Programme, says if the blockade isn't resolved there will be higher prices, famine, more migration and political unrest.
He tweeted that "2022 was already going to be a year of unprecedented hunger ... If the Odesa ports remain closed as the July harvest is coming in, it will be a declaration of war on global food security".
On the ground in Ukraine, Russia at the weekend was throwing everything at gaining all of the Luhansk and Donetsk regions - known as the Donbas - in the east of the country as the Kyiv Government pushed for more heavy, long-range weapons from the West.
In a call between Vladimir Putin and Italian Prime Minister Mario Draghi, the Russian President made it clear Moscow's price for cooperation over the food crisis is an easing of Western sanctions. Russia is in control of much of Ukraine's coastline, deploying about 20 vessels, including submarines.
The vast majority of Ukraine's grain normally goes through the Black Sea. The country and the EU has been looking into moving more grain across land and river. Via the railway system, Ukraine is only exporting up to 1.5 million tonnes a month.
There have been calls for a convoy of vessels to shift the grain from Odesa, which would appear to be risky politically and militarily unless emergency shipments can be kept separate from the wider conflict.
Reuters reported Turkey is in talks with Russia and Ukraine to open a safe shipping route via the Bosphorus Sea for grain exports from Ukraine.
Some agreement to send grain out from Odesa in a non-military, humanitarian operation is the best that can be hoped for.
The war, like the pandemic, is highlighting global economic monopolies and countries' interdependence.
Aside from grain and cooking oils, the war has caused a shake-up of energy strategies and demand as Western Europe tries to avoid Russia's coal and gas.
During the early stages of the pandemic, China's status as a major exporter of manufactured goods and particularly medical supplies caused problems - setting off a mad scramble for PPE. Then later, with Europe and the US dominating vaccine research and production, countries in Asia and Africa were slow to get rollouts underway.
And just in May, the US had to fly in baby formula from Europe after shortages at home.
The world is getting a recurring, old lesson: the danger of having too many eggs in one basket.
