Very likely, the whole hatred will revolve around taxes.
I'm thinking that the global trading house approached the kingdom for certain trading rights, and expecting a large influx of taxes, the government agreed. However, when the ruler put out his hand expecting a large sum of money, all he recieved was a pitance. When an explination was demanded, the trading house claimed it was paying only what was due of them by contract; they had very poor sales in the country. This has been ongoing for years, and though the merchant house has been doing well, the ruler feels he is being slighted in what he is due.
The last staw came in the midst of war. For lack of funds, a major battle was lost. Furthermore, the trading house was trading goods with "the enemy". Despite its prostetations of its neutrality and that it has been long trading with every known country, the kingdom sees the act as treasonous. The ruling body has decided it is not only the trading house's fault, but the government seeks to seize the assets it believes are rightfully theirs - and then some, damn the consequences.