SPOILOR TREAD FOR HIGURASHI ( Talk about spoilers here... NOT AT GB)

A powerful miko named Hanyuu is born and treated as a demon because of her horns.
- Hanyuu chooses to bear all the sins of the villagers herself and have her daughter, Ouka kill her with the Onigari no Ryuoh.
- Through sarifice Hanyuu becomes a deity who watches over the area. Deeds she did contributed to the legend and worship of Oyashiro-sama.
- Over time Hanyuu's powers faded until even the Furude's could no longer see her.
- Dr. Takano discovers the Hinamizawa Syndrome and devotes his life researching it.
- Tanashi's parents die and she is put through hell in an orphanage.
- Dr. Takano rescues her and she becomes fascinated with his research
.- Dr. Takano presents his findings to the government but his work is ridiculed.
- Dr. Takano commits suicide.- Tanashi changes her name to Takano and devotes her life to continuing her grandfather's research.
- Takano uses her connections with Koizumi to push forward a project for researching Hinamizawa Syndrome.
- Mion and Shion are born, with Mion being born first. She becomes the heir to the Sonozakis.
- Mion and Shion occasionally swap places. Shion accidentally gets marked with the demon tattoo instead of Mion. Unable to reverse the situation, Shion becomes Mion and Mion becomes Shion.
- Rika is born, as the 8th successive Furude female. She's Oyashiro-sama's reincarnation, allowing her to see Hanyuu.
- Reina moves out of Hinamizawa.
- Government starts a dam project in Hinamizawa.
- Houjos go against the Sonozakis and anger the other citizens of Hinamizawa. Houjous become hated by everyone.
- Akasaka visits Hinamizawa and Rika tells him of her upcoming death.
- Yamainu kidnap the minister's grandson to suspend the dam project.
- The dam manager succumbs to the syndrome and attacks his fellow workers, he is killed in retaliation.
- The 5 workers agree to cut up in the body into 5 parts and keep them hidden.
- A live specimen is needed to advance Hinamizawa Syndrome's research. Takano brings in one of the dam workers suffering from L5.
- The dam manager's mutilated body is found and the 4 other workers are arrested. The manager was like a second-father to Ooishi.
- Ooishi swears to find the person responsible for the manager's death and return the right arm that went missing.
- Rika's dad informs his wife and daughter about Hinamizawa Syndrome and how Rika is the Queen.
- Rika volunteers to be Irie and Takano's guinea pig to save Hinamizawa from the syndrome.- An emergency response plan is set up. So the government can wipe out the villagers in case everyone goes berserk.
- Satoko suffers from the syndrome and isolates herself from everyone but Satoshi and begins to believe her own parents want to kill her.
- Satoshi undergoes heavy stress from having Satoko constantly rely on him. Irie convinces him to join the baseball team he's manager for to help relieve stress.
- Satoko goes with her parents on a vacation and pushes them off a viewing platform.
- Satoko and Satoshi are pushed in the hands of their aunt and uncle. The aunt and uncle abuse Satoko and Satoshi.
- Satoko is brought into the clinic and is discovered to have L5.
- Rika convinces Irie to use the experimental medicine C103 on Satoko.
- Satoko recovers to L3 and is released from the hospital, while maintaining daily injections and weekly visits.
- Oishi tries to interrogate Satoko, believing her parents death is connected to manager's death.
- Rika's parents interfere with the research on her daughter.
- Takano has the Yamainu kill Rika's parents.
- Reina blames herself for her parents divorce. She's begins cutting herself as punishment.
- Reina is almost raped at her old school and snaps, nearly killing them.
- Reina is put on a strong medication.
- Mion starts the club games for Satoko's sake, to help erase her loneliness.
- Reina hears Hanyuu apologizing and believes all her misfortune to be Oyashiro-sama's curse.
- Reina moves back to Hinamizawa and changes her name to Rena.
- Shion falls in love with Satoshi.
- Satoshi is stressed as ever, now hearing Hanyuu's footsteps.
- Satoshi kills her aunt to help Satoko.
- Shion tries to cover up Satoshi's murder and has 3 nails ripped out as punishment.
- Irie picks up Satoshi after he bought a huge bear for Satoko's birthday. Satoshi begins clawing at his throat. Irie takes him to the clinic.
- Mion rips out 3 of her nails too for Shion's sake.
- Rika and Satoko live together with Irie paying for their expenses.
- Mion confronts Oyrou about Satoshi's disappearance.
- Keiichi goes around shooting kids with a bb gun. Until one day he accidentally shoots a little girl in the eye and turns himself in.
- Koizumi passes away and the government loses interest in Hinamizawa Syndrome. The project will be suspended in three years.
- Takano is approached by a mysterious woman, offering her a way to achieve her goal and get back at those who ridiculed Dr. Takano's work.
- Oyrou realizes the hate for the Houjos will go away quicker if new people move in, Sonozakis sell off some land.
- Keiichi's dad tours Hinamizawa and talks with Rika and Hanyuu. This convinces him to move there.
- Keiichi moves to Hinamizawa.

In episode 13 when Satoko falls into the storage room when they were playing hide and seek, there was a guy who looked almost exactly like a younger Keiichi. o_O
He's older than Rika and Satoko so he can't really be that person because he was just as small as Rika and Satoko in that picture, but maybe he was just short. O_o
That could be why he shot those kids, he had "Hinamizawa Syndrome" from leaving Hinamizawa.
...That could just be something the anime put in to confuse people though. I don't remember seeing anyone like that in the game.

In Tatarigoroshi-hen how Keiichi went to kill Satoko's uncle so he didn't go to the festival.
Then the club members all said that Keiichi went to the festival... It's not true they were all trying to make a alibi for Keiichi...
Then Satoko said her uncle is still alive... That's not true either... She just is still thinking that her uncle is alive.
Nobody died because Keiichi wished them to

Mion and Rena dug up Teppei's corpse or something and then made up the alibi for him...
Satoko thinks he is still alive because she has L5 and sees all men Teppei's age as Teppei. And maybe because she's colour blind and has L5 they look more similar to her...

The corpse at the start was Mamiya Rina
That is why Satoko's uncle came to get Satoko...

Takano's scrapbooks are all made up
When people suffer the 'Hinamizawa Syndrome' they can start to hear (not see) Hanyuu (hear Hanyuu's footsteps etc.)

the footsteps

Mion's gun is not a real gun it's a model gun but it can still fire...
Rika wants bigger breasts
Satoko can't tell the difference between broccoli and cauliflower
Akasaka calls his daughter Miyuki
There was a rumor at Hinamizawa saying that Ooishi is 'Oyashirosama's assistant

he always wants to know about the murders and things they were not supposed to do and those things were "against Oyashiro-sama's will". Oyashiro-sama will "punish" them for going against his will and Ooishi can arrest them or something.

Edit~ oh they had contact with him before they disappeared... well they are paranoid when they have "Hinamizawa Syndrome" and Ooishi just wants to investigate or something, and they become even more paranoid, and then they hear the footsteps of "Oyashiro-sama"/Hanyuu and thought that it was Oyashiro-sama trying to punish them or something, and thought that it was Ooishi's fault or something.

D: run-on sentence again.